_______________________________
А) 4 + 5 1/4 = 4 + 21/4 = <u>4*4 +21</u> = <u>16 +21</u> = 37/4 = 9 1/4
4 4
б) 1 2/9 + 3 1/3 = 11/9 + 10/3 = <u>11 + 10*3</u> =<u> 11 +33</u> = 44/9 = 4 8/9
9 9
в) 1 3/5 + 2 2/3 = 8/5 + 8/3 = <u>8*3 + 8*5</u> = <u>24 + 40</u> = 64/15 = 4 4/15
15 15
г) 5 3/4 - 2 = 23/4 - 2 = <u>23 - 2*4</u> = <u>23-8</u> = 15/4 = 3 3/4
4 4
д) 3 - 5/7 = <u> 3*7 - 5</u> =<u> 21 - 5</u> = 16/7 = 2 2/7
7 7
е) 4 - 1 7/9 = 4 - 16/9 =<u> 4*9 - 16</u> =<u> 36 - 16</u> = 20/9 = 2 2/9
9 9
ж) 3 2/5 - 3/5 = 17/5 - 3/5 = <u>17 - 3 </u>= 14/5 = 2 4/5
5
з) 4 1/3 - 1 1/2 = 13/3 - 3/2 = <u>13*2 - 3*3</u> =<u> 26 - 9</u> = 17/6 = 2 5/6
6 6
1/2=0,5=50%
1/4=0,25=25%
3/4=0,75=75%
2/5=0,4=40%
17/50=0,34=34%
2/(3×8) - (2×8)/3 = (2-2×8×8)/(3×8) =
- 126/24 = - 63/12
Ответ А