Question

помогите пожалуйста​

Answer 1

Пошаговое объяснение:

1.

7/15 ÷7/12=7/15 •12/7=4/5=0,8

21/15 ÷15=7/5 •1/15=7/75

6/17 ÷1=6/17

2 3/11 ÷5/9=25/11 •9/5=(5•9)/11=45/11=4 1/11

3 9/20 ÷23=69/20 •1/23=3/20=0,15

2 1/12 ÷1 5/36=25/12 •36/41=(25•3)/41=75/41=1 34/41

2/7 ÷3 1/2=2/7 •2/7=4/49

24 12/17 ÷4=420/17 •1/4=105/17=6 3/17

2.

х - задуманное число.

(х +1/3)•8 1/18 -1 1/9=15-8 7/19

(х +1/3)•8 1/18 -1 1/9=14 19/19 -8 7/19

(х +1/3)•8 1/18=6 12/19 +1 1/9

(х +1/3)•8 1/18=6 108/171 +1 19/171

(х +1/3)•8 1/18=7 127/171

(х +1/3)=1324/171 •18/145

х=2648/2755 -1/3=7944/8265 -2755/8265=5189/8265

3.

(1 3/7)^2 •(7/10)^3 •(8/21 +1/3)^2=(10/7)^2 •(7/10)^3 •(8/21 +7/21)^2=10^(2-3) •7^(-2+1) •(5/7)^2=(5•2)^(-1) •7^(-1-2) •5^2=5^(-1+2) •2•7^(-3)=(5•2)/7^3=10/343