Question

1.descompuneti nr 390 in nr direct proportionale cu 3,4,6
2.descompuneti nr 420 in nr invers proportionale cu 2,8,4 ​

Answer 1

Răspuns:

1.

a/3 = b/4 = c/6 = k

a=3k

b=4k

c=6k

13k=390 =>k=30

a=90

b=120

c=180

2.

2a=8b=4c=k

a = k/2

b = k/8

c = k/4

4k+k+2k=420×8

7k=420×8

k=480

a=240

b=60

c=120