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Misha Larkins [42]
3 years ago
8

Jonathan counted a

Mathematics
1 answer:
Svetach [21]3 years ago
6 0

Answer:

36 White cars

Step-by-step explanation:

total of 40 white cars and yellow cars"      means     40 = W + Y

 "9 times as many white cars as yellow cars"   means  9Y = W

   9W + 9Y = 360        (first equation; multiply (W+Y=40) by 9 to eliminate Y)

   W   - 9Y  = 0           (carefully revise the second equation)

 -------------------   (Elimination method:  add the equations)

   10W      = 360

      W  =  36       Ans:  36 White cars

Checking (very important):

   40 = W + Y

   40 = 36 + Y

   4 = Y

 is    9(4) = 36

        36 = 36

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