Arithmetic Progression Sum

If the nth term of an AP is (2n+1) then the sum of its first three terms is

• 6n+3

• 15

• 12

• 21

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

• 6

• 9

• 15

• -3

If the first term of an AP is –5 and the common difference is 2, then the sum of the first 6 terms is

• 0

• 5

• 6

• 15

The famous mathematician associated with finding the sum of the first 100 natural numbers is 

•  Euclid

• Newton

• Pythagoras 

•  Gauss 

How many terms of the arithmetic series 18 + 15 + 12 +...have to be taken so that it sum is zero.
Which formula can be used

• Tn 

• Sn = n/2 [a + Tn]

• Sn = n/2 [2a + (n-1)d]

Find the sum of 2+4+6+.....+200

• 108

• 10100

• 40703

• -8930

Find the sum of 20 terms of the AP 1,4,7,10, .....

Find the sum of the following arithmetic prgression 50,46,42, .... to 10 terms

• 320

• 144

• 525

• 162

Find the sum of last ten terms of the AP 8,10,12,14, ....,126

• 1176

• 1234

• 1123

• 1170

Find the sum of the following AP -37,-33,-29,.... to 12 terms

• -200

• -180

• -160

• -120