Question

d+1/5=4/7+3/7;f+4/5=4/7+3/7;b+2/5=4/7+3/7;

Answer 1

д+1/5=4/7+3/7
д+1/5=1
д= 1- 1/5
д=4/5
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f + 4/5=4/7+3/7
f+4/5=1
f=1- 4/5
f=1/5
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b+2/5=4/7+3/7
b+2/5=1
b=1- 2/5
b=3/5
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