How to show the estimate of 3 multiplied by the power of 10

3x10x10x10x10=30000 or 3 × 10^4 = 3 × 10 × 10 × 10 × 10 = 30,000 hope this helps you give thanks

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