Use compatible numbers to estimate the quotient394.6 divided by 9

45

Step-by-step explanation:

As a first rough estimate:  divide 390  by 10, obtaining 39.

Another reasonable approximation could be obtained by dividing 450 by 9 and 360 by 9, obtaining 50 and 40.  Since 390 is roughly halfway between 360 and 450, estimate that the quotient is approx 45 (halfway between 40 and 50).

the answer is b.)

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