6.3 Arithmetic Series

Evaluate the arithmetic series described:
2 + (-2) + (-6) + (-10)..., S₁₀

• -160
• -328
• -320
• -336

Evaluate the arithmetic series described:
11 + 18 + 25 + 32..., S₇

• 225
• 450
• 384
• 224

Find the sum of the 1st 20 terms: 2+5+8+......

• 1220

• 610

• 600

• 612

Find the sum of the 1st 100 terms: 100+98+96+......

• 100

• 1000

• 50

• -98

Find the sum: 11 + 15 + 19 + .......+ 83

• 19

• 83

• 893

• 624

Find S_n for the given series:
a₁=22
d=-8
n=21

• 1911
• -1449
• -2436
• -1218

Find S₁₄ 
7, 2, -3, ...

• -812
• 119
• -945
• -357

Find the sum of first 20 even numbers.

• 400

• 410

• 420

• 430

Find the sum : 8+12+16+20+24+28+32+36+40