The number of minutes it take to complete the same job if sandy and randy work together than if sandy works alone is 18mins.
According to this question, Sandy rakes and bags the leaves on her front lawn in 30 mins while Randy does the same job in 20 mins.
To calculate the time it will take both of them to work together, we use the following expression;
1/30 + 1/20 = 1/x
x = 12mins
Therefore, it will take 30 - 12 = 18 mins, to complete the same job if sandy and randy work together than if sandy works alone.
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