So represent missing number with x
x means unknown so
x+-1=+1
adding a negative means subtraction
x-1=1
you can do anything to an equation as long as you do it to both sides
add 1 to both sides
x+1-1=1+1
x+0=2
x=2
the number is 2
Answer:
15 18 21 are the answer hope it's useful
Amount of room hannah can paint in an hour = 1/20
amount of room destiny can paint in an hour = 1/16
number of hours = x
1/20x + 1/16x = 1
the reason why this formula is true is, the amount of the room painted in the end should be 1 (the whole room)
4/80x + 5/80x = 1
9/80x = 1
9x = 80
x = 80/9 hours
x = 8.89 hours
One hundred eighty-seven and twenty-three thousandths
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