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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 551 is correct. Excellent, bobbym!

552. The line joining the points (2,1) and (5,-8) is trisected at the points P and Q. If the point P lies on the line 2x - y + k = 0, find the value of k.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 552 is correct. Brilliant, bobbym!

553. The digits of a positive number, having three digits, are in an Arithmetic Progression and their sum is 15. The number obtained by reversing the digits is 594 less than the original number. Find the number.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 553 is correct. Excellent, bobbym!

554. Find the lengths of the medians of a triangle ABC whose vertices are A(-1,3), B(1,-1), and C(5,1). Also, find the coordinates of the centroid of the triangle ABC.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 554 is correct. Magnificent, bobbym!

555. Solve:

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 555 is correct. Excellent, bobbym!

556. (a) If sin (A - B) = 1/2 and cos (A + B) = 1/2, then find A and B.

556. (b) If cos (A + B) = 0 and sin (A - B) = 1/2, then find A and B.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 556 (four parts) is correct. Excellent, bobbym!

557. Three unbiased coins are thrown simultaneously. Find the probability of getting

a) 3 tails

b) 2 tails

c) no tails

d) 2 heads and 1 tail

e) at least 1 head.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 557 (five parts) is correct. Excellent, bobbym!

558. A metallic sphere of radius 10.5 cm is melted and then recast into small cones, each of radius 3.5 cm and height 3 cm. Find how many such cones are obtained.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 558 is correct. Excellent, bobbym!

559. If

divides exactly, find a and b.Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 559 is correct. Excellent, bobbym!

560. A cylindrical jar of radius 6 cm contains oil. Iron sphere each of radius 1.5 cm are immersed in oil. How many spheres are necessary to raise the level of the oil in centimeters?

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

I think the problem is ambiguous. Regretted. I have posted a fresh problem.

560 a. Name the type of quadrilateral formed, if any, by the following points, and give reasons for your answer.

(4,5), (7,6), (4,3), and (1,2).

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 560 is correct. Excellent, bobbym!

561. From a group of 2 boys and 3 girls, two children are selected at random. Find the probability of

(i) both selected children are are girls.

(ii) the selected group consists of one boy and one girl.

(iii) at least one boy is selected.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,042

Hi;

The solution 561 is correct. Excellent, bobbym!

562. From the top of a building 60 m high, the angles of depression of the top and bottom of a vertical lamp post are observed to be 30 degrees and 60 degrees respectively. Find

(i) the horizontal distance between the building and the lamp post.

(ii) the height of the lamp post.

Take

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 107,739

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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