First, let's organise the info and use algebra!
Let x represent the number of sit ups Abby can do in a minute.
121 sit ups = 8 minutes
x sit ups 1 minute
x sit ups = 121 sit ups x 1 minute ÷ 8 minutes
x sit ups = 15.125
x sit ups = ~15
Therefore, Abby can do ~15 sit ups in one minute.
Hope this helps!
