How do you find percents and convert stuff!?!?!?!?

Question

I'm working on my summer math, but i'm stumped please help me. I need help with these questions.

a) What is 85% of 800? b) 44 is what percent of 132?

c) 90 is 75% of what? D) What is 5% of 40? and

Convert the following to a decimal:

a) 7/8

b) 5.6 %

Answer 1

a)

85% is 85/100.  Since you want 85% of 800 set up the following equality and solve for x:

(85/100) = (x/800)

800(85/100) = x

8*85 = x

680

Then 680 is 85% of 800.

b)

You want to find what percent, x%, and percent is out of 100 so you want to find x / 100 which corresponds to 44 / 132.  Set up the following equality and solve for x:

(x/100) = (44/132)

x = 100(44/132)

x = 33.33

Then 44 is 33.33% of 132.

c)

75% is 75/100.  Since you want 90 to be 75% of something, x, set up the equality and solve for x:

(75/100) = (90/x)

x(75/100) = 90

x = 90(100/75)

x = 120

Then 90 is 75% of 120.

d)

5% is 5/100.  Since you want 5% of 40 set up the following equality and solve for x:

(5/100) = (x/40)

40(5/100) = x

2 = x

Then 2 is 5% of 40.

a)  7/8 = 1.75

b)  5.6% = 5.6/100 = .056

Hope this helps you!