% Type 2

% Solved!

Type #2

The good old “What is 32% of 60” type of question. This is a common percent question and one that we use regularly.

I have:   A  percent value

I have:    1 number

     I need to find:   A 2^nd number, which is a certain percent of the 1st number.

Examples:             a) What is 75% of 640?

b) Prices rose by 25% last year. If a TV cost $600.00 last year, what does it cost this year? (What is 25% of $600.00 added to the price?)

c) She got a 15% discount on the books. If the books cost $400.00 originally, what is the discounted price? (What is 15% of $400.00 subtracted from the price?)

Key to Solving:

All three questions above are “percentage of” questions. For question 1 above:

Step 1 – change the 75% to 75

                                             100

Step 2 – Cross out the word “of” with an “X”. This becomes your multiplication sign.  

75   X

100

Step 3 – Divide 75 by 100, then multiply by 640.

75   X  640 = 480

100

Tricks to look out for.

a) Prices rose by 25% last year. If a TV cost $600.00 last year, what does that TV cost this year?

ý  Wrong! 25 ÷ 100 x $600.00 = $150.00       The TV costs 150 dollars.

þ Right!   25 ÷ 100 x $600.00  = $150.00      $600.00  PLUS  $150.00 = $750.00.

You need to add the 25% value (in this case, $150.00) because the price ROSE or went up.

b) She got a 15% discount on the books. If the books cost $400.00 originally, what is the discounted price?

ý Wrong!  15 ÷ 100 x $400.00 = $60.00   The books cost $60.00.

þ Right!   15 ÷ 100 x $400.00 = $60.00      $400.00 MINUS $60.00 = $340.00   The books cost $340.00. You need to subtract the 15% value (in this case $60.00) because the prices were discounted.