Question

There are only HB and F type pencils in the store. The ratio of the number of HB to F is 7 : 3. If there are 15F type pencils, how many pencils are there altogether?

Answer 1

50

Explanation:

Ratio is

• 7 : 3

Total number is

• 7x + 3x = 10x

Since F type pencils number is known:

• 3x = 15
• x = 15/3
• x = 5

Then total number is:

• 10x = 10 *5 = 50