Question 887320
Using his riding lawnmower, John can mow a baseball field in two hours. John’s son, Logan, using a 
smaller lawnmower, can mow the same field in five hours. How long would it take them to mow the 
baseball field working together?
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let x=time it would take them to mow the baseball field working together?
1/2=John's work rate
1/5=son's work rate
1/x=work rate working together
sum of indv. work rates=work rate working together
..
{{{1/2+1/5=1/x}}}
{{{5/10+2/10=1/x}}}
7/10=1/x
x=10/7
How long would it take them to mow the baseball field working together? 10/7 hrs