Question

Trey has money saved for a school trip. he earns an additional $40 mowing lawns to add to his savings. trey’s parents give him enough money to double the amount he has so far for the trip. now trey has a total of $234 for the trip.

a. write and solve an equation to find the amount trey had saved before mowing lawns.
b. how would this compare with an arithmetic approach to this problem?

Answer 1

The answer is 77 dollars.

If you do 234 divided by 2, you would get 117 dollars, which is the amount that Trey's parents gave him if they gave him double the amount he had saved up after he got the extra 40 dollars from moving lawns. Then, you would do 117 minus 40 to get you 77 dollars he had already had previously saved up.

Answer 2

x= amount he has saved

x+40 +(x+40)=234

x= saved amount plus 40 he saved mowing lawns plus the amount his parents give him is 234

2x+80 = 234

subtract 80 from both sides

2x = 154

divide each side by 2

x=77

he had 77 saved before he mowed lawns

b) I am not sure what they mean. I am thinking you would have to guess a starting value for trey and calculate and see if you got the right answer. kind of like quess and check. you would need to do this many times before you got the right answer