Tìm X
a) (X x 7 + 8) : 5 = 10 b) (X + 5) x 19 : 13 = 57 c) 4 x (36 – 4 x X) = 64 d) 7,6 : 1,9 x X = 3,2 e) (X : 2 + 50) : 5 = 12 |
g) 280 : (7 + 3 x X) = 4
h) 6 x (28 – 8 x X) = 72
i) (X – 15 ) x 3 : 12 = 6
k) (X : 4 + 6) x 7 = 70
l) 5 x (7 + 3 x X) = 140
a) \(\left(x.7+8\right):5=10\)
\(x.7+8=10.5\)
\(x.7+8=50\)
\(x.7=50-8\)
\(x.7=42\)
\(x=42:7\)
\(x=6\left(tm\right)\)
Vậy ......................
b) \(\left(x+5\right).19:13=57\)
\(\left(x+5\right).19=57.13\)
\(\left(x+5\right).19=741\)
\(x+5=741:19\)
\(x+5=39\)
\(x=39-5\)
\(x=34\left(tm\right)\)
Vậy ..................
c) \(4\left(36-4x\right)=64\)
\(36-4x=64:4\)
\(36-4x=18\)
\(4x=36-18\)
\(4x=18\)
\(x=\dfrac{18}{4}\)
Vậy ....................
d) \(7,6:1,9.x=3,2\)
\(4x=32\)
\(x=32:4\)
\(x=8\left(tm\right)\)
Vậy ................
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