Answer :
70% = 0,7 = 7/10
7/10 * x = 35 | (*10/7)
7/10 * 10/7 * x = 35/1 * 10/7 7/10 * 10/7 => 1
1x = 35/1 * 10 / 7
x = (35*10)/7
x = 350 / 7
x = 50
7/10 * x = 35 | (*10/7)
7/10 * 10/7 * x = 35/1 * 10/7 7/10 * 10/7 => 1
1x = 35/1 * 10 / 7
x = (35*10)/7
x = 350 / 7
x = 50