Answer :
f + 2b = 92
3b + 4f = 212
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You didn’t say you need them solved, but just in case:
f = 92 -2b
3b + 4(92-2b) = 212
3b + 368 -8b = 212
-5b = -156
b = 31.20
f + 2(31.20) = 92
f + 62.4 = 92
f = 29.60
3(31.2) + 4(29.6) = 93.6 + 118.4 = 212
3b + 4f = 212
———————————
You didn’t say you need them solved, but just in case:
f = 92 -2b
3b + 4(92-2b) = 212
3b + 368 -8b = 212
-5b = -156
b = 31.20
f + 2(31.20) = 92
f + 62.4 = 92
f = 29.60
3(31.2) + 4(29.6) = 93.6 + 118.4 = 212