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UKMT Junior Kangaroo, 2019

Algebra Difficulty 1.0 Junior Find the answer United Kingdom

The mean of five numbers is 25. Abbie adds 5 to the first number, 10 to the second number, 15 to the third number, 20 to the fourth number and 25 to the fifth number to obtain a new set of five numbers. What is the mean of the numbers in the new set?

(A) $100$ (B) $50$ (C) $40$ (D) $30$ (E) $25$

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