12 men : 8 hours : 10 days
// Find if every man works 1 hour
12 x 8 men : 1 hour : 10 days
96 men : 1 hour : 10 days
//Find if every man works 15 hours
96 ÷ 15 men : 15 hours : 10 days
6.4 men : 15 hours : 10 days
//Find if every man works 1 day
6.4 x 10 men : 15 hours : 1 day
64 men : 15 hours : 1 day
//Find if every man works 8 days
64 ÷ 8 men : 15 hours : 8 days
8 men : 15 hours : 8 days
Answer: 8 men is needed
Given the equation :

We will use estimation to find the value of the given expression
So, the best estimation for the number 576 is = 600
The best estimation for the number 8 is = 10
So, the given expression is approximately = 600 ÷ 10 = 60
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We can calculate the error of the approximation as following :
The actual value is : 576 ÷ 8 = 72
So, the difference is = 72 - 60 = 12
so, the percentage of error will be :

Answer:
36 boards
Step-by-step explanation:
The boards are as long as the room, so I only had to worry about the width. If the boards were 1/2 ft wide, I would need 2 boards for every foot of width. For 16 ft, I would need 32 boards.
Instead of dividing, I wrote the equivalent multiplication by multiplying by the reciprocal of 11/24 (the reciprocal of 11/24 is 24/11)
I simplified by dividing both 2 and 24 by 2, and both 11 and 33 by 11.
Therefore he needs 36 boards