Arithmetic by L Key

If 4, x₁,x₂,x₃,28 are in AP then x₃ is ______

• 19

• 23

• 22

• cannot be determined.

The sum of first 'n' terms of an AP is (3n²+6n). The common difference of the AP is ______

• 6

• 9

• 15

• -3

Formula to find sum of n terms in an AP is ________

• sn = a+ (n - 1)d

• $s_n$ = $\frac{n}{2}$ (2a +(n-1)d)

• $s_n$ = $\frac{n}{2}$ (2a +(n+1)d)

What is the common difference of an AP in which a₁₈ - a₁₄ = 32?

• 8

• -8

• 4

• -4

If 7 times the 7th term of an AP is equal to 11 times its 11th term, then its 18th term will be 

•  7 

•  11 

•  18 

• 0

The following are Arithmetic Progressions, except

• 12, 6, 3, ...

• 4, 2, 0, ...

• x, x+2, x+4, ...

• -4

• -2

• 0

• 2

The 7^th term of an AP is 3 times the 2^nd term, find a relation between a and d.

How many terms of the AP 2, 7, 12, ... will add up to 156?

• 7

• 8

• 9

• 10