The sum (S) of the first,n, positive integers(S=1+2+3+....+N) is S=n(n+1)over 2. Without using a calculator, determine the sum of the first 1000 multiples of 5: 5+10+15+........+5000.
The title of the page is solve a simpler problem!!!!!!
The title of the page is solve a simpler problem!!!!!!
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Notice first that 5+10+15+...+5000=5*(1+2+...+1000). Now we can use your formula to find:
5+10+15+...+5000=5*(1000*1001)/2=25025…
Hope this helps :)
5+10+15+...+5000=5*(1000*1001)/2=25025…
Hope this helps :)
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Your formula is wrong you have s = n/2( n + 1) should be n/2(n + Last term)
a = first term, d = common difference, n number of terms, L= last term. s = sum
sum = n/2{a + L}
or s = n/2(2a + [n - 1]d)
your first term a = 5, n = 1000 and d = 5
Just evaluate using the second formula above
a = first term, d = common difference, n number of terms, L= last term. s = sum
sum = n/2{a + L}
or s = n/2(2a + [n - 1]d)
your first term a = 5, n = 1000 and d = 5
Just evaluate using the second formula above