science homework: 1/2 hour
math homework:1/3
total: sum of both time periods
so, 1/2+1/3
first we find the LCM of 2 and 3 as they are denominators and for addition of fractions denominators have to be the equal amount.
LCM of 2 and 3 is 6
so, now we have to make denominators equal so we have to figure out much will we multiply with 2 and 3 to get 6 so,
1x3/2x3 + 1x2/3x2
which would equal = 3/6 + 2/6
=5/6
now if u need to find the answer in fraction its 5/6 but, if u need it in proper amounts it would be:
5/6 of an hour(60 minutes)
5/6 of 60
which would be, 60x5/6
=50 minutes
thus, earl spent 50 minutes in total doing his homework.