Question 183872
G = Number of gloves
B = Number of bats
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(a)  B + G = 28
(b)  29*G + 14*B = 647
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Solve (a) for B = 28 - G
Substitute into (b)
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29*G + 14*(28-G) = 647
29*G + 392 - 14G = 647
15G = 255
G = 17
B = 28 - 17 = 11


Hope that helps!