243 + 62-28 = n
243 + 34 = n
277 = n
n= 277
Answer:
40
Step-by-step explanation:
here is a trig calculator
http://www.carbidedepot.com/formulas-trigright.asp
Answer:
He did 9 times 10 instead of 9 times 100.
Estimation for addition: 86 rounds up to 90 and 17 rounds up to 20 so:
90 + 20 = 110
Estimation for subtraction is the same thing but with subtraction
90 - 20 = 70
Now for the exact answers:
86 + 17 = 103
86 - 17 = 69
Your answers are 110, 70, 103, and 69.
