"30 percent of 122 equals 85.4" is false. 30 percent of 122 equals 36.6.
(7 percent of 21) - (4 percent of 21) = 0.63
21/30 x 100 = 70. Therefore, 21 is 70 percent of 30.
Given 20 and 50%, multiply 20 by 0.5, which equals 10. Given 70 and 30%, multiply 70 by 0.3, which equals 21. Or if you prefer, given 20 and 50%, multiply 2 by 5, which equals 10. Or if you prefer, given 70 and 30%, multiply 7 by 3, which equals 21.
21 of 62 is 33.87%
40% + 30% = 70%
21 is 30% of 70
21
21
21
5.71%
30%