Heya!
2/0.5=4
You can check your work by multiplying 0.5*4.
Answer : 4.5 × 10⁴ square inches can be washed per hour.
Step-by-step explanation :
As we are given that an area can be washed at a rate of 4,900 cm²/min. Now we have to determine the square inches can be washed per hour.
Given conversions are:
1 cm = 0.39 in and 1 hr = 60 min
As, 1 cm² = (0.39)² in² and 1 min = 1/60 hr
So, 

Now we have to determine the square inches can be washed per hour.
As, 
So, 
Therefore, 4.5 × 10⁴ square inches can be washed per hour.
Hey there Rosy! I did this recently and the answer is:
1 : 4
2 to 8
18
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72