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Find the value of 16 + 17 + 18 + ....... + 75

A2600

B2850

C2520

D2730

Answer:

D. 2730

Read Explanation:

16+17+18+........+75=S75−S1516+17+18+........+75=S_{75}-S_{15}

S75=n(n+1)/2=75(76)/2=2850S_{75}=n(n+1)/2=75(76)/2=2850

S15=n(n+1)/2=15(16)/2=120S_{15}=n(n+1)/2=15(16)/2=120

16+17+18+...+75=2850−120=273016+17+18+...+75=2850-120=2730

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