Question

Round each value to the nearest 10 and find an estimate of the expression:

Answer 1

Look

124 when you round it to nearest 10 you get 120

38  when you round it to nearest 10 you get 40

71 when you round it to nearest 10 you get 70

207 when you round it to nearest 10 you get 210

Now add them up

120 + 40 + 70 + 210 =

So answer is 440  

I hope u understand

Answer 2

Note: to round to the nearest ten, look to the first place digit. if it is 5 or greater, round up, if 4 and lower, round down

124 rounded to the nearest ten = 120
38 rounded to the nearest ten = 40
71 rounded to the nearest ten = 70
207 rounded to the nearest ten = 210

120 + 40 + 70 + 210 = 120 + 110 + 210 =  230 + 210 = 440

440, or C is your answer

hope this helps