Question

What is the sum of the first twenty consecutive numbers?​

Answer 1

Answer:

We have to calculate, 1+2+3+4+….+20

First term = 1

Last term = 20

Total number of terms = n = 20

Using formula, sum of n terms = Sn = n/2(first term + last term)

= 20/2 (1 + 20)

= 210

Step-by-step explanation:

hope this helps you

Answer 2

Answer:

Always remember that the sum of first 10 consecutive numbers is 55

It helps a lot

so

the sum of first twenty consecutive numbers:

= 55 + 10 + 11 + 12 + 13 ... + 20

= 55 + (10+1) + (10+2) + (10+3) ... (10+10)

= 55 + 55 + 100 ( 55 because the first ten numbers are being repeated and 100 because there is an extra set of ten 10's which when added becomes 100)

= 110 + 100

= 210 (answer)

This is the simplest method

I hope it helps :)