Answer:
S = 3741
Step-by-step explanation:
Here, we want to calculate the sum of the first 86 numbers (starting from 1)
Mathematically, we can use the formula;
Sn = n/2[ a + L]
Where n is the number of terms (86 here)
a is the first term which is 1 and L is the last term which is 86
So, we have the sum as;
Sn = 86/2(1 + 86) = 43 * 87 = 3741
