Question

Nr a si b sunt invers proportinale cu 0,25 si0,2 aflati nr stiind ca 8a+2b=132

Answer 1

a x 0,25 = b x 0,2 = k

a = k/0,25 = k x 100/25 = 4k

b = k/0,2 = k x 10/2 = 5k

8a+2b = 132

8x4k + 2x5k = 132

32k + 10k = 132

42k = 132

k = 132/42 = 22/7

a = 4 x 22/7  = 88/7

b = 5 x 22/7 = 120/7