394.6 divided by 9 using compatible numbers to estimate the quotient?

394.6 / 9 = 43.84

Compatible numbers:

400 / 10 = 40

Compatible numbers are numbers that can quickly be solved mentally. The quotient would only be an estimate since we only rounded the number to the nearest compatible number.

394.6 is nearer to 400 while 9 is closer to 10. Both numbers 400 and 10 are compatible because they can be solved quickly doing mental calculations.