Answer:
$110
Step-by-step explanation:
Let a, b, and c represent the earnings of Alan, Bob, and Charles. The problem statement tells us ...
a + b + c = 480 . . . . . . the combined total of their earnings
-a + b = 40 . . . . . . . . . . Bob earned 40 more than Alan
2a - c = 0 . . . . . . . . . . . Charles earned twice as much as Alan
Adding the first and third equations, we get ...
(a + b + c) + (2a - c) = (480) + (0)
3a + b = 480
Subtracting the second equation gives ...
(3a +b) - (-a +b) = (480) -(40)
4a = 440 . . . . . . . . simplify
a = 110 . . . . . . . . . . divide by the coefficient of a
Alan earned $110.
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<em>Check</em>
Bob earned $40 more, so $150. Charles earned twice as much, so $220.
The total is then $110 +150 +220 = $480 . . . . as required
We can use the ratios for special triangles (see the attachment below). We'll be using the 45-45-90 triangle. We notice that side BC is equal to

, and side AC (x using the special right triangle) is equal to 16. We can therefore say that side BC is equal to

ft
:)
2/1
Step-by-step explanation:
_1/3y=_1
y=_1+3/1
y=2/1
You multiply 3/4 by 2/3 it equals 2/4 which equals 1/2. The answer is 1/2.