Question

(48:6+a):8=27:9
(20:a+20):6=50:10
(a:4+5):2=24:4
a:7+(36:6-21:7)=7
(64-3×8-5×a):2=10

Answer 1

(48 : 6 + a) : 8 = 27 : 9, (8 + a) : 8 = 3, 8 + a = 3 x 8, 8 + a = 24, a = 24 - 8
a = 16

(20 : a + 20) : 6 = 50 : 10, (20 : a + 20) : 6 = 5, 20 : a + 20 = 5 x 6,
20 : a + 20 = 30, 20 : a = 30 - 20, 20 : a = 10, a = 20 : 10
a = 2

(a : 4 + 5) : 2 = 24 : 4, (a : 4 + 5) : 2 = 6, a : 4 + 5 = 6 x 2, a : 4 + 5 = 12,
a : 4 = 12 - 5, a : 4 = 7, a = 7 x 4
a = 28

a : 7 + (36 : 6 - 21 : 7) = 7, a : 7 + (6 - 3) = 7, a : 7 = 7 - 3, a : 7 = 4, a = 4 x 7,
a = 28

(64 - 3 x 8 - 5 x a) : 2 = 10, (64 - 24 - 5 x a) = 10 x 2, 40 - 5 x a = 20,
5 x a = 40 - 20, 5 x a = 20, a = 20 : 5
a = 4