let x be how much longer she can run the race and still beat her previous time
55(min) + x(min) < 1(hr) + 10(min)
55(min) + x(min) < 60(min) + 10(min)
55 + x < 60 + 10
x < 60 + 10 - 55
x < 15(min)
The answer is 70 . if it is 75 or higher then it wold be rounded to 80