Verified answer

№ 3. (2 3/5 - 5/8) : 19 3/4 = 1/10

1) 2 3/5 - 5/8 = 13/5 - 5/8 = 104/40 - 25/40 = 79/40

2) 79/40 : 19 3/4 = 79/40 : 79/4 = 79/40 * 4/79 = 4/40 = 1/10 = 0,1

№ 4. 9 2/7 * 1 2/5 : 13 + 6 3/7 = 7 3/7

1) 9 2/7 * 1 2/5 = 65/7 * 7/5 = 65/5 = 13

2) 13 : 13 = 1

3) 1 + 6 3/7 = 7 3/7

№ 5. 9 4/5 : (4 2/3 * 10 1/2) = 1/5

1) 4 2/3 * 10 1/2 = 14/3 * 21/2 = 7 * 7 = 49

2) 9 4/5 : 49 = 49/5 : 49 = 49/5 * 1/49 = 1/5 = 0,2

№ 6. 6 2/3 : (4/5 - 7/20) = 14 22/27

1) 4/5 - 7/20 = 16/20 - 7/20 = 9/20

2) 6 2/3 : 9/20 = 20/3 : 9/20 = 20/3 * 20/9 = 400/27 = 14 22/27