Answer :
Tanisha takes 5/6 hours longer to mow all the lawns last week than this week.
Here, we are given that Tanisha mowed 5 lawns last week in 7/ 12 hours each.
Thus, the total time taken by her to mow 5 lawns = 5(7/12)
= 35/ 12 hours
Now, this week she mows the five lawns in 5/12 hours each
Thus, the total time taken by her = 5(5/12)
= 25/12 hours
Therefore, the difference between the time taken by her last week and this week will be-
35/ 12 - 25/ 12
= (35 - 25)/ 12
= 10/ 12
= 5/6
Thus, Tanisha takes 5/6 hours longer to mow all the lawns last week than this week.
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