What is a good estimate for the solution to the equation x3 = 95 how do you come up with your estimate

Hi! I'm guessing, for now, that you mean x-to-the-third = 95. You might also have meant 3x=95. (Or something else less obvious, in which case of course you can follow-up.) I'll make suggestions for both.

If it's x-to-the-third, it helps if you can memorize a few of the most basic numbers-to-a-power, but it's also not necessary. 2-to-the-third is 2*2*2, or 8 -- much too low. 3*3*3 is 27, still low. 4*4*4 is 64 -- now we're getting closer. 5*5*5 is 125, and now we're too high. So I'd estimate that x is about 4 and a half.

(If you were watching me say those out loud, I'd just say them fast, like 4*4*4 is the most obvious thing in the world. That's because I've solved that one many times. You can memorize them if you want to, or just figure them out from scratch.)

If you meant 3x = 95, well, let's see. 3*3 = 9. So 90, which is ten times bigger because there's an extra zero at the end, must be 3*30. Then 95 is only a bit bigger than 90, so my estimate is "a bit over 30".

The amount used= 13.04- 1.9 = 11.14