At a country concert, the ratio of the number of boys to the number of girls is 2:5. If there are 250 girls, how many boys are at the concert?

There are 100 boys at the concert

Step-by-step explanation:

If the the ratio of  boys to girls is 2:5 and and there are 250 girls  then a number was multiplied by 5 to get 250  and that number needs to be multiply by 2  to find the number of boys.

So to find that number we will divide 250 by 5.

250/ 5 = 50  

50 * 2 = 100