You bought a magazine for $2.10 and some erasers for $4.60 each. you spent a total of $15.90. how many erasers did you buy

$15.90 - $2.10 = 13.8
13.8/4.60= 3
4.60(3) + 2.10= 15.90

According to the math when u do 15.90 - 2.10 u get 13.80. Then do 4.60x3 u get 13.80 which means he or she bought 3 erasers

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