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#1 Re: Help Me ! » Proof Check » Yesterday 19:38:56

hi Au101

That looks good to me.  smile

Well done.

Bob

#3 Re: Help Me ! » Mandy Jane's Corner » Yesterday 06:28:14

I am preparing a large post.  Give me 10 minutes.

Bob

#5 Re: Introductions » hi » Yesterday 04:18:34

hi iluvdogs

Welcome to the forum.  Glad you like the site.  smile

Agnishom wrote:

What is your favorite color?

Obviously, not paying attention.  Surely the correct question to ask is:

What is your favourite breed of dog ?

Bob

#6 Re: Help Me ! » Difficult partial fractions and/or difficult integral » Yesterday 04:15:27

Au101 wrote:

I never really knew how to do that, but thanks bob bundy, that way's much easier.

I just thought, why did they ask for that substitution, unless it made the integral easier.  So in what way ? Thinks .......  Ah ha! 

Bob

#10 Re: Help Me ! » inverse function » 2014-08-19 22:35:36

hi Ramesh ra,

This graph will show you:

2YDnHP4.gif

The blue curve is y = x^2, and the red curve is y = √x

The line y = x is the mirror line that will reflect one curve into the other.  This always happens with a pair of inverse functions.

eg.  (2,4) is on y = x^2   and (4,2) is on y = √x

Hope that helps,

Bob

#11 Re: Help Me ! » Mandy Jane's Corner » 2014-08-19 22:25:42

[math]\frac{?}{?}= 0.?? = ??\%[/math]

#14 Re: Help Me ! » The circumference vs. area of a circle. » 2014-08-19 07:10:15

hi

9asGEab.gif

I get BAD = 115.9 and ABC = 64.1   Notice that they add up to 180  (why?).

Your question asks for the acute angle.

Bob

#21 Re: Help Me ! » Mandy Jane's Corner » 2014-08-19 03:27:42

hi Mandy,

Oh that is so good.  They are all correct.  So now I'll leave out more and you have to fill in more numbers.

[math]\text{Q21.   } \frac{7}{8} = \frac{? \times ??}{? \times ??}= \frac{??}{100}= ??[/math]

[math]\text{Q22.   } \frac{7}{40} = \frac{? \times ??}{? \times ??}= \frac{??}{100}= ??[/math]

Here are some peoples' marks in tests.  Convert the marks into percentages.  Set them out in the usual way.

Q23.   27/40

Q24.   49/50

Q25.   456/600

Bob

#22 Re: Help Me ! » Mandy Jane's Corner » 2014-08-18 06:37:41

Yes all correct!

[math]\text{Q16.   } \frac{3}{8} = \frac{3 \times ??}{8 \times 12.5}= \frac{??}{100}= ??[/math]

[math]\text{Q17.   } \frac{5}{8} = \frac{5 \times ??}{8 \times ??}= \frac{??}{100}= ??[/math]

In these ones the bottom number is bigger than 100, so we divide to reduce down to 100.

[math]\text{Q18.   } \frac{52}{200} = \frac{52 \div ??}{200 \div 2}= \frac{??}{100}= ??[/math]

[math]\text{Q19.   } \frac{44}{400} = \frac{44 \div ??}{400 \div 4}= \frac{??}{100}= ??[/math]

[math]\text{Q20.   } \frac{55}{500} = \frac{55 \div ??}{500 \div ?}= \frac{??}{100}= ??[/math]

Bob

#23 Re: Help Me ! » Mandy Jane's Corner » 2014-08-18 06:26:39

Correct.  5 more coming up

Bob

#25 Re: Help Me ! » Mandy Jane's Corner » 2014-08-18 05:34:02

Excellent.  These three are all correct.

For Q14 the bottom number (20) must be times by something  to make 100.

You can find the number by doing this on a calculator:

Once you have this number, times the top by the same.

For Q15 you can do a similar thing.

So do

Hope that helps.

Bob

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