E. Fill in the missing number to make each equation correct.
21.8 x _ = 1 x 8
22. 20 x ( 4 += (20 x 4) + (20 x 3)
23. 9 + (6 + 5 ) = (9 + 6) +
24.7 x ( 10 + 5 ) = ( 5 x 10 ) + ( 7 x 50 )
25. 24 + ( 36 + 50 ) = ( + ) + 50​