Bob has some 10 lb weights and some 3 lb weights. Together, all his weights add up to 50 lbs. If x represents the number of 3 lb weights and y represents the number of 10 lb weights, which equation can be used to find the number of each type of weight Bob has?

Question

boldjon · Answer

50 + 10y = 3y

tgannon998 · Answer

10x +3y=50

medicaldoctor · Answer

3x + 10y = 50

medicaldoctor · Answer

@Tgannon998 and @boldjon I do not see how you came up with your answers from the information given?

tgannon998 · Answer

same way you came up with yours.

medicaldoctor · Answer

Right but you have to be careful because your answer is wrong. Your variables are mixed up.

tgannon998 · Answer

it doesnt matter what is labeled X or Y.

medicaldoctor · Answer

Actually it does matter because the problem specifically says what to label them. y = 10 lbs and x = 3 lbs

tgannon998 · Answer

It does the same thing.

medicaldoctor · Answer

@mathmale am I making sense here? And it doesn't actually because the problem would be different if you had what it says and the variables you put down. Just be careful.

medicaldoctor · Answer

Plugging in information correctly is key to Algebra, and simple math.

tgannon998 · Answer

you still get the same answer.

medicaldoctor · Answer

No you will not because you are plugging in 3 times the amount of 10 lbs and 10 times the amount of 3 lbs.

medicaldoctor · Answer

Since we have 3x for our weights the amount of weight total of the 3lb weights is going to be three times. This is why we need to use x.

texaschic101 · Answer

it has to be 3x + 10y = 50....because x represents 3 lb....and y represents 10 lb

medicaldoctor · Answer

We have 10y because the amount of weight total will be ten times the amount of weights. This is why y is important. And exactly @texaschic101