Math Is Fun Forum
  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#1 Re: Ganesh's Puzzles » 10 second questions » Today 00:41:12

Hi;

The solutions in #5846 are correct. Neat work, bobbym!

#5847. 12 defective pens are accidentally mixed with 132 good ones. It is not possible to just look at the pen and tell weather or not it is defective. One pen is taken out at random from this lot. Determine the probability that the pen taken out is a good one.

#2 Re: Ganesh's Puzzles » Oral puzzles » Today 00:26:31

Hi;

The solutions (two parts) is #3016 are correct. Excellent, bobbym and Monox D. I-Fly!

#3017. If

evaluate

#3 Re: Ganesh's Puzzles » General Quiz » Today 00:10:35

Hi;

The Answer #6043 is correct. Neat work, bobbym!

#6045. What is a 'portmanteau'?

#6046. What is the origin of the word 'academy'?

#5 Re: Ganesh's Puzzles » English language puzzles » Yesterday 16:43:32

Hi;

Both the Answers, #2521 and #2522, are correct. Splendid, bobbym!

#2523. What does the noun calyx mean?

#2524. What does the verb (used with or without object) camber mean?

#6 Re: Ganesh's Puzzles » Series and Progressions » Yesterday 16:28:22

Hi;

The solution SP#246 is correct. Neat work, bobbym!

SP#247. Find the sum of all 3 digit numbers which are divisible by 11.

#7 Re: Dark Discussions at Cafe Infinity » crème de la crème » Yesterday 00:12:17

139. John J. Loud

John Jacob Loud (November 2, 1844 – August 10, 1916) was an American inventor known for designing the first ballpoint pen.

Trained as a lawyer at Harvard College, Loud worked at the Union National Bank in Weymouth, Massachusetts as a cashier. He was also active in his community as a member of his church, a trustee of many local organizations, and as a member of local historical societies. Loud invented and obtained a patent for what is considered to be the first ballpoint pen in 1888; however his invention was not commercialized and the patent would eventually lapse. The modern ballpoint pen would be patented later in 1938, 22 years following Loud's death.

Early life and career

Loud was born in Weymouth, Massachusetts in 1844, the son of John White Loud and Sarah Humphrey Blanchard. He attended school in Weymouth, graduating from Weymouth High School, and later attended Harvard College, graduating from the latter in law in the class of 1866. Appointed to the Suffolk County Bar on February 2, 1872, he later furthered his studies in law in the office of Jewell, Gaston & Field, but later opted to join his father in the banking profession. In 1871 he joined his father in working for the Union National Bank as an assistant cashier. Upon his father's death in 1874, Loud assumed his position as cashier, and remained in that post until his resignation in 1895 for health reasons.

Inventions

Keenly interested in inventing, on October 30, 1888, Loud obtained the first patent (US #392,046) for a ballpoint pen when attempting to make a writing instrument that would be able to write on leather products, which then-common fountain pens could not. Loud's pen had a small rotating steel ball, held in place by a socket. In the patent, he noted:

    My invention consists of an improved reservoir or fountain pen, especially useful, among other purposes, for marking on rough surfaces-such as wood, coarse wrapping-paper, and other articles where an ordinary pen could not be used.

Although his invention could be used to mark rough surfaces such as leather, as he had originally intended, it proved to be too coarse for letter-writing. With no commercial viability, its potential went unexploited and the patent eventually lapsed.

Loud had also registered patents for a firecracker cannon (1888) and a "toy cannon" (1887).

Personal life, death

Residing in Weymouth, Loud was a member of the Union Congregational Church. He was an active genealogist, and an active member of the Maine Genealogical Society, New Hampshire Genealogical Society, New England Historic Genealogical Society, and Weymouth Historical Society (of which he was a founding member). He was a descendant of Francis Loud, originally of Ipswich, Massachusetts, and Mayflower passengers William Brewster and John Alden. Loud also was a trustee of the Weymouth Savings Banks, Tufts University Library and the Derby Academy, and a conductor of the Union Religious Society choir at Weymouth and in Braintree. A noted orator, he spoke at many local events, including delivering an address upon the building of the first warship at the Fore River Shipyard in 1900. He also wrote poetry and songs in his spare time. One of his sisters, Annie Frances Loud, was a locally noted composer of "sacred music".

He was married to Emily Keith Vickery from November 7, 1872 until her death in November 1911. The couple had eight children. He died at his home in Weymouth on August 10, 1916 and was buried at Village Cemetery in Weymouth.

john-jacob-loud.JPG

#8 Re: Ganesh's Puzzles » English language puzzles » 2016-05-22 23:31:57

Hi;

The Answer #2520 is correct. Good work, bobbym!

#2521. What does the noun calypso mean?

#2522. What does the noun camaraderie mean?

#9 Re: Ganesh's Puzzles » Series and Progressions » 2016-05-22 23:15:52

Hi;

The solution SP#245 is correct. Excellent, bobbym!

SP#246. Find the sum of all two digit natural numbers which are divisible by 4.

#10 Re: Ganesh's Puzzles » Oral puzzles » 2016-05-22 17:49:05

Hi;

The solution #3015 (a) is correct. Neat work!

#3016. If sin A = 3/4, calculate cos A and tan A.

#11 Re: Ganesh's Puzzles » 10 second questions » 2016-05-22 17:32:10

Hi;

The solution #5845 (three parts) are correct. Good work, bobbym!

#5846. Five cards - the ten, jack, queen, king, and ace of diamonds, are well shuffled with their face downwards. One card is then picked at random.
(i) What is the probability that the card is the queen?
(ii) If the queen is drawn and put aside, what is the probability that the second card picked up is (a) an ace? (b) a queen?

#12 Re: Ganesh's Puzzles » Series and Progressions » 2016-05-22 17:11:38

Hi;

The solution SP#244 is correct. Remarkable, bobbym!

SP#245. Find the sum of all natural numbers between 40 and 400 which are divisible by 7.

#13 Re: Ganesh's Puzzles » English language puzzles » 2016-05-22 17:01:46

Hi;

Both the Answers, #2517 and #2518, are correct. Marvelous, bobbym!

#2519. What does the noun Calvados mean?

#2520. What does the noun Calvinism mean?

#14 Re: Ganesh's Puzzles » General Quiz » 2016-05-22 16:37:24

Hi;

The Answer #6042 is correct. Neat work, bobbym!

#6043. What is 'the Great Patriotic War'?

#6044. The Geneva Convention relative to the Protection of Civilian Persons in Time of War, commonly referred to as the Fourth Geneva Convention and abbreviated as GCIV, is one of the four treaties of the Geneva Conventions. When was it adopted?

#15 Re: Ganesh's Puzzles » English language puzzles » 2016-05-22 00:39:24

Hi;

The Answer #2515 is correct. Neat work, bobbym!

#2517. What does the noun callus mean?

#2518. What does the noun calumny mean?

#16 Re: Ganesh's Puzzles » General Quiz » 2016-05-22 00:14:06

Hi;

The Answer #6039 is correct. Good work, bobbym!

#6041. Name the city known as "The Garden of England".

#6042. Where is "The Great White Way"?

#17 Re: Ganesh's Puzzles » 10 second questions » 2016-05-21 23:50:56

Hi;

The solution #5844 (three parts) are correct. Neat work, bobbym!

#5845. One card is drawn from a well-shuffled of 52 cards. Find the probability of getting
(i) the jack of hearts.
(ii) a spade.
(iii) the queen of diamonds.

#18 Re: Ganesh's Puzzles » Oral puzzles » 2016-05-21 23:36:05

Hi;

The solution set in #3014 is correct. Magnificent, bobbym!

#3015. If

find the values of the following trigonometric ratios:

#19 Re: Ganesh's Puzzles » Series and Progressions » 2016-05-21 23:14:47

Hi;

The solution SP#243 is correct. Excellent, bobbym!

SP#244. Find the sum of all odd numbers between 10 and 200.

#20 Re: Ganesh's Puzzles » English language puzzles » 2016-05-21 19:07:01

Hi;

Both the Answers, #2513 and #2514, are correct. Excellent, bobbym!

#2515. What does the noun calligraphy mean?

#2516. What does the adjective callow mean?

#21 Re: Ganesh's Puzzles » General Quiz » 2016-05-21 18:51:40

Hi;

Both the Answers, #6037 and #6038, are correct. Brilliant, bobbym!

#6039. Name the Filipino politician who served as the 11th President of the Philippines  (January 25, 1933 – August 1, 2009). She was the most prominent figure of the 1986 People Power Revolution, which toppled the 20-year authoritarian rule of President Ferdinand E. Marcos and restored democracy to the Philippines. She was named Time magazine's "Woman of the Year" in 1986. Prior to this, she had not held any other elective office.

#6040. Name the capital of Laos.

#22 Re: Ganesh's Puzzles » 10 second questions » 2016-05-21 18:24:05

Hi;

The solution #5843 (two parts) are correct. Excellent, bobbym!

#5844. One card is drawn from a well-shuffled of 52 cards. Find the probability of getting
(i) a king of red color.
(ii) a face card.
(iii) a red face card.

#23 Re: Ganesh's Puzzles » Oral puzzles » 2016-05-21 18:12:17

Hi;

The solution set in #3013 is correct. Good work, bobbym!

#3014. Solve:


#24 Re: Ganesh's Puzzles » Series and Progressions » 2016-05-21 18:03:05

Hi;

The solution SP#242 is correct. Well done, bobbym!

SP#243. Find the sum of integers between 200 and 300 that are divisible by 7.

#25 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2016-05-21 01:10:35

138. Al-Khwārizmī

Al-Khwārizmī, in full Muḥammad ibn Mūsā al-Khwārizmī (born c. 780—died c. 850) Muslim mathematician and astronomer whose major works introduced Hindu-Arabic numerals and the concepts of algebra into European mathematics. Latinized versions of his name and of his most famous book title live on in the terms algorithm and algebra.

Al-Khwārizmī lived in Baghdad, where he worked at the “House of Wisdom” (Dār al-Ḥikma) under the caliphate of al-Maʾmūn. The House of Wisdom acquired and translated scientific and philosophic treatises, particularly Greek, as well as publishing original research. Al-Kwārizmī’s work on elementary algebra, Al-Kitāb al-mukhtaṣar fī ḥisāb al-jabr waʾl-muqābala (“The Compendious Book on Calculation by Completion and Balancing”), was translated into Latin in the 12th century, from which the title and term Algebra derives. Algebra is a compilation of rules, together with demonstrations, for finding solutions of linear and quadratic equations based on intuitive geometric arguments, rather than the abstract notation now associated with the subject. Its systematic, demonstrative approach distinguishes it from earlier treatments of the subject. It also contains sections on calculating areas and volumes of geometric figures and on the use of algebra to solve inheritance problems according to proportions prescribed by Islamic law. Elements within the work can be traced from Babylonian mathematics of the early 2nd millennium bce through Hellenistic, Hebrew, and Hindu treatises.

In the 12th century a second work by al-Khwārizmī introduced Hindu-Arabic numerals (see numerals and numeral systems) and their arithmetic to the West. It is preserved only in a Latin translation, Algoritmi de numero Indorum (“Al-Khwārizmī Concerning the Hindu Art of Reckoning”). From the name of the author, rendered in Latin as Algoritmi, originated the term algorithm.

A third major book was his Kitāb ṣūrat al-arḍ (“The Image of the Earth”; translated as Geography), which presented the coordinates of localities in the known world based, ultimately, on those in the Geography of Ptolemy (flourished 127–145 ce) but with improved values for the length of the Mediterranean Sea and the location of cities in Asia and Africa. He also assisted in the construction of a world map for al-Maʾmūn and participated in a project to determine the circumference of the Earth, which had long been known to be spherical, by measuring the length of a degree of a meridian through the plain of Sinjār in Iraq.

Finally, al-Khwārizmī also compiled a set of astronomical tables (Zīj), based on a variety of Hindu and Greek sources. This work included a table of sines, evidently for a circle of radius 150 units. Like his treatises on algebra and Hindu-Arabic numerals, this astronomical work (or an Andalusian revision thereof) was translated into Latin.

alkhwarizmi.jpg

Board footer

Powered by FluxBB