Question

There are 90 million pet dogs in the US. The number of dogs is 1000% the number of reptiles. How many reptiles are there?

Answer 1

There are 9 000 000 = 9 million reptiles in the US.

Explanation:

Percentages and ratio:

The double of a measure, for example, is 200% of the measure.

So 1000% of a measure is 10 times the measure.

There are 90 million pet dogs in the US. The number of dogs is 1000% the number of reptiles.

The number of pet dogs is 10 times the number of reptiles, which means that:

`10x = 90 000 000`

`x = (90 000 000)/(10)`

`x = 9 000 000`

There are 9 000 000 = 9 million reptiles in the US.