Question

find the sum of all even numbers between 1 and 150​

Answer 1

Answer:

a = 2

An = 148 (between 1 and 150 so 150 is not included)

d = 2

An = a + (n-1)d

148 = 2 + (n-1)2

146/2 = n-1

73 = n-1

n = 74

Sn = n/2 (a + An)

S74 = 74/2 (2+148)

S74 = 37×150 = 5550

Sum of even numbers is 5550.

#WMK

Answer 2

Answer:

5550

Step-by-step explanation:

Using Sn = n (a1 + an)/2

a1 = 2

a2 = 150

n = $\frac{a2}{2}$ - 1          (Because 150 is not included)

n = 74

74 × $(\frac{( 2 + 150)}{2})$

This gives you 5550