I'm not sure that I am 100% right but I'll give it a shot.
50+75= 125*0.35=43.75
$43.75
1. 538 - 247 = ?
2. 8 - 7 = 1
3. You can't subtract 3 and 4, so you have to take number from 5 (turning it into a 4) and then you add a 1 right next to 3 (which makes it 13;13 - 4 = 9
4. 4 - 2 = 2
538 - 247 = 291
So the answer is 291.
If you would like to solve (n^3 - n^4) - (3n^3 - 7n^4), you can do this using the following steps:
(n^3 - n^4) - (3n^3 - 7n^4) = <span>n^3 - n^4 - 3n^3 + 7n^4 = n^3 - 3n^3 - n^4 + 7n^4 = -2n^3 + 6n^4
</span>
The correct result would be <span>-2n^3 + 6n^4.</span>
This is just stuff you have to memorize, I can’t really explain much further than product always means multiplication. The “product of” means k*m