80 minutes
Step-by-step explanation
Step 1
to solve this we need to do a subtraction
time left= total movie -minutes he watched
then
replace

so, the answer is 77 minutes
Step 2
What is the estimated number of minutes left if both numbers are rounded to the tens place?
hence, we need to round the numbers and then do the subtraction

so

so, the answer is 80
I hope this helps you