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Algebra Difficulty 1.8 Junior Find the answer

What is the value of 13+23+33+431^{3}+2^{3}+3^{3}+4^{3}?

A number or a short expression. Spacing and $ signs are ignored.

Solution

Expanding and simplifying, 13+23+33+43=1×1×1+2×2×2+3×3×3+4×4×4=1+8+27+64=1001^{3}+2^{3}+3^{3}+4^{3}=1 \times 1 \times 1+2 \times 2 \times 2+3 \times 3 \times 3+4 \times 4 \times 4=1+8+27+64=100. Since 100=102100=10^{2}, then 13+23+33+43=1021^{3}+2^{3}+3^{3}+4^{3}=10^{2}.

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