# Word Problem on Proportions

#### crappiefisher26

##### New member
Kevin earned $165 interest for 1 year on an investment of$1500. At the same rate, what amount of interest would be earned by and investment of $2500. 165/1500=2500/x i then cross multiplied 1500 times 2500 and got 3,750,000 then got 3750000/165 x=22727.27273 would that be right? if not let me know what i did wrong so i can fix it, would x= simplify to$22,727

#### TchrWill

##### Full Member
Kevin earned $165 interest for 1 year on an investment of$1500. At the same rate, what amount of interest would be earned by and investment of $2500. 165/1500=2500/x i then cross multiplied 1500 times 2500 and got 3,750,000 then got 3750000/165 x=22727.27273 would that be right? if not let me know what i did wrong so i can fix it, would x= simplify to$22,727
You started out right but got switched in mid stream.

Assuming simple interest, 166/1500 = x/2500

I'm sure you can take it from here.

#### Denis

##### Senior Member
crappiefisher26 said:
Kevin earned $165 interest for 1 year on an investment of$1500. At the same rate, what amount of interest would be earned by and investment of $2500. 165/1500=2500/x i then cross multiplied 1500 times 2500 and got 3,750,000 then got 3750000/165 x=22727.27273 would that be right? if not let me know what i did wrong so i can fix it, would x= simplify to$22,727
Crappy, use a bit of common sense:
are you ready to pay me $22,727 in interest if I lend you$2,500 for a year :?: :shock:

#### Mrspi

##### Senior Member
crappiefisher26 said:
Kevin earned $165 interest for 1 year on an investment of$1500. At the same rate, what amount of interest would be earned by and investment of $2500. 165/1500=2500/x i then cross multiplied 1500 times 2500 and got 3,750,000 then got 3750000/165 x=22727.27273 would that be right? if not let me know what i did wrong so i can fix it, would x= simplify to$22,727
You made a common mistake in setting up the problem. Your first fraction is

interest / investment
165 / 1500

Shouldn't the second fraction be set up the same way?

interest / investment
x / 2500

NOW the two fractions are equal, and you can proceed to solve by cross-multiplying:

165 / 1500 = x / 2500

1500x = 165(2500)

See if this gives you a more reasonable answer.