Question

300-297+294-291+288-285+...+6-3

Answer 1

300 - 297 = 3

294 - 291 = 3

288 - 285 = 3

So, that is a sequence of sums of number 3: 3 + 3 + 3 + .... + 3

How may times will the number 3 be added?

Note that 300 is reduced in 6 units each time => 300 / 6 = 50 => 3 will be added 50 times.

=> 50 * 3 = 150

Answer: 150