Use rounding or compatible numbers to estimate the sum of 63+71

Since both are 2 digit numbers, round to the nearest tens place.

63 round to 60 since 3 is less than 5.
71 round to 70 since 1 is less than5.

Add the rounded numbers.

60+70=130

Final 130

In all honesty, there really is no “work” per say to show. mainly it’s just using the process of elimination. the question is asking which domain(s) would be the most appropriate for the function c(n). n is the number of observed vehicles so right away, 1, 2, and 3 can be eliminated.why? 1, 2 start in the negatives and therefore it is impossible to observe negative cars. so, #4 would be the best answer to the given problem.