Find the sum of the first 42 terms of the following series, to the nearest integer.
2,7,12,...

Step-by-step explanation:

Find the sum of the first 42 terms of the following series, to the nearest integer.

2,7,12

Solution

The sum is given by  

SUM_n=n/2*(a_1+a_n)

a_n=a_1+(n-1)d

a_1=2,   n=42,     d=5

The 42nd term is therefore given by  

a_42=2+(42-1)5=207

SUM_42=42/2*(2+207)=21*209=4389

The sum of the first 42 terms of the series, therefore, is 4389

.632

step-by-step explanation:

6 * 1/10 = 3/5

3*0.01 = 0.03

3/5 + 0.03 = .63

2*0.002 = .002

.63 + 0.002 = .632

step-by-step explanation:

the true ones are a b and d