Question

найдите неизвестный член пропорции 7/9/3,1=х:9,3

Answer 1

7/9      х
---- = -----
3,1     9,3

3,1х = 7/9 * 9,3
3,1х = 7/9 * 93/10
3,1х = 651/90
х = 651/90 : 3,1
х = 651/90 : 31/10
х = 651/90 * 10/31
х = 21/9 = 2 3/9 = 2 1/3

Answer 2

7/9:3,1=х:9,3
3,1х=9,3*7/9
3,1х=93/10*7/9
3,1х=217/30
х=217/30:3,1
х=217/30:31/10
х=217/30*10/31
х=7/3
х=2 1/3