What is the sum of all of the perfect squares between #15# and #25#, inclusive, minus the sum of all of the other numbers between #15# and #25,# inclusive?

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Subject: Pre-Algebra
Focus: Squares

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Answer 1 · 2018-06-14T05:06:37

#-138#

The only perfect squares between 15 and 25 inclusive are #16 and 25#

#:.# Sum of perfect squares #=16+25 = 41#

The sum of the natural numbers between #17 and 24# is given by:

#S_8 = 8/2(17+24) = 4xx41 =164#

#:.# Sum of the other numbers #=15+164 = 179#

We are asked for the sum of perfect squares minus the sum of the other numbers:

Sum #= 41-179= -138#