Question
What is the value of 143 +
163 + 183 + … + 303?Solution
143 + 163 + 183 + .... + 303 =8(73 + 83 + 93 + …. + 153) Sum of n cubes = (n(n + 1)/2)2 for n=6 we have 212 = 441 for n=15 we have1202 = 14400 Difference=14400-441 =13959 Therefore 8*13959=111672
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