math

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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!

  • math -

    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.

  • math -

    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 %

  • math -

    Both are right! :-)

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