Answer: E
Explanation:
In order to find the sum of consecutive numbers, we always follow three steps:
- Find the number of numbers
- Find the middle number
- Multiply
The multiples of five between 23 and 92 are really the numbers starting from 25 and ending with 90. To find the number of numbers, subtract 25 from 90, divide by 5, and add 1:
90 – 25 = 65
65/5 = 13
13 + 1 = 14
2. Find the middle number:
The middle number between 25 and 90 is the average of 25 and 90:
25 + 90 = 115
115/2 = 57.5
3. Multiply:
57.5*14 = 805
The answer and explanation to GMAT Practice Question #20 was written by Integrated Learning, a company that provides professional and private one on one tutoring services.
