Let n = the first of three consecutive numbers.
Let n + 1 = the second consecutive number, and ...
Let n + 2 = the third consecutive number.
Since we're given that: "the sum of three consecutive numbers is 210," then we can now translate this statement mathematically into the following equation to be solved for the unknown number n:
n + (n + 1) + (n + 2) = 210
n + n + 1 + n + 2 = 210
Collecting like-terms on the left, we get:
3n + 3 = 210
3n + 3 - 3 = 210 - 3
3n + 0 = 207
3n = 207
(3n)/3 = 207/3
(3/3)n = 207/3
(1)n = 69
n = 69
Therefore, ,...
n + 1 = 69 + 1 = 70 and
n + 2 = 69 + 2 = 71
CHECK:
n + (n + 1) + (n + 2) = 210
69 + (70) + (71) = 210
69 + 70 + 71 = 210
210 = 210
Therefore, the three consecutive numbers whose sum is 210 are indeed 69, 70, and 71, and 71 is obviously the largest of these three numbers