If A = 1 – 10 + 3 – 12 + 5 – 14 + 7 + … upto 60 terms, then what is the value of A?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4, i.e. –270
A = 1 – 10 + 3 – 12 + 5 – 14 + 7 + … upto 60 terms
=(1 – 10) + (3 – 12) + (5 – 14) + .......30 terms
= –9 – 9 – 9 – 9 .......30 times
A = – 9 × 30 = – 270