Using compatible number estimate 212+347

Ok so basically what you have to do is really read the question carefully and understand the question they are trying to ask you and basically compatible numbers are numbers that are basically close to the actual sum and so let say this problem for instance lets try to round 212 to 210 and 347 to 350 and if you add you compatible numbers you would get 560 and if you actually add the problem itself you would get you get 559 and that is literally a 1 digit difference and that is really close and so the best estimate for this problem would be 560 and the actual answer is 559 and so yeah if you compare them it would be really close and so thank you for giving me this question and hpe this helped you out!!

The volume is 2212m cubed

Add up all the sides