The johnson twins were born seven years after their older sister. this year, the product of the three siblings' ages is exactly 3334 more than the sum of their ages. how old are the twins?

The twins are 13 , 13x13x20=3380 and 13+13+20=46 , 3380-46=3334

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post