Question

Bob and Fred together make $20.00 a week less than double John. John makes $110.00 a week and Bob makes $140.00 a week. How much does Fred make? answer

Answer 1

Fred makes $60/week.

Explanation:

Fred makes f dollars per week, john j dollars and bob b dollars.

Then b = $140/week; j = $110/week; and b + f = 2j - 20.

Substitute $140/week for b in this equation; also substitute $110/week for j. Then:

$140/week + f = 2($110) - $20. There's only one variable here, f, so we're ready to solve for f:

$140/week + f = $220/week - $20/week, or:

$140/week + f = $200/week

Subtract $140 from both sides, obtaining:

f = $60

Fred makes $60/week.

Answer 2

If both Bob and Fred make $20 less a week than twice John's weekly salary, then

`B+F+20 = 2*J`,

where B, F, and J are Bob's, Fred's, and John's salaries, respectively.

We want to find F, Fred's salary. Plugging in Bob's and John's salaries, we obtain

`140+F+20 = 2*110`

`F+160 = 220`

`F = 60`

So Fred makes $60 a week.