1. Tính
5\(\frac{7}{8}\)x 6 \(\frac{3}{5}\)=......................................................
2 . Tìm x
( x - 4 ) * 3 = 21
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Dấu * là dấu nhân nhé!
\(5\frac{7}{8}\times6\frac{3}{5}=\frac{47}{8}\times\frac{33}{5}=\frac{155}{4}\)
( x - 4 ) x 3 = 21
x - 4 = 7
x = 3