how do you solve 5x + 2=90?

Question

Leila ran in a 5- kilometer race to raise money. Each sponsor donated $2.00 for each kilometer that she ran. She raised $90.000. How many sponsors did she have?

 

I set up the equation 5x+2=90, is this correct?

Answer 1

Since the sponsors donated $2.00 per km and she ran 5 km that would be $2 x 5 = $10 per km.

So, with the total be $90, the equation would be $10 X x = $90. (the large X is a times sign and you are solving for the small x)

Answer 2

Well your equation is close, but not correct.  It should be:

 

$90 = ($2 per km)*(5 km)*(x sponsors)

 

$90 = $10*x

 

$90/$10 = x

 

9 sponsors = x

Answer 3

The total is 90,000 dollars so instead of 9, she would need 9000 donors at 10 dollars each.