Question

If you know that 8×300=2,400, how can you find 8×320? Explain.

Answer 1

we have

$8*300=2,400$

we know that

$320=(300+20)$

so

$8*320=8*(300+20)=8*300+8*20$

substitute the value of $8*300=2,400$

$8*320=2,400+8*20=2,400+160=2,560$

Answer 2

If 8x300=2,400, then 8x320 would equal 2,560. Why? Because 8x20=160. 2,400+160=2,560.
Hope this helps! :)