Question

Please can u help me with number two please I'm so lost and I don't know on what to do

Answer 1

All you have to do to find 40*50 in your mind, is multiply 4 and 5. Then you will have to add the two 0s at the end. So it will go like 4*5=20+0+0=2,000

Answer 2

you would know 4×5=20 so just add 2 more zeroes cause there is a zero in 40 and in 50

hope this is what you're looking for and made sense