# math

What is the formula for finding these??

1. 30 % of 90

2. 70 is 10 % of what?

3. 4/10 of 30

4. change 2/8 to a percent

Please help me with these formulas! Thanks!

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asked by lucy
1. The word "of" means multiply.

Change the percent to a decimal.

30% * 90 = 0.3 * 90 = 27

0.1 x = 70
x = 70/0.1 = 700

I'll be glad to check your answers for the other problems.

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2. so.. 3. 4/10 of 30=

4/10 x 30/1=12

and 4. 2/8 to % would be 8 into 2 which equals .25= 25 %

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posted by lucy
3. Both are right! :-)

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