# Summations problem

elainehula

## Homework Statement

Sum all the whole numbers which are multiples of 5 from 5 to 1550

## The Attempt at a Solution

1550÷5=310
1550-5x310= 478950

Science Advisor
Homework Helper
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## Homework Statement

Sum all the whole numbers which are multiples of 5 from 5 to 1550

## The Attempt at a Solution

1550÷5=310
1550-5x310= 478950

Hint: Sum of arithmetic progression or, alternatively,$$\sum_{k=1}^{310}5k = 5\sum_{k=1}^{310}k$$

Science Advisor
Homework Helper

## Homework Statement

Sum all the whole numbers which are multiples of 5 from 5 to 1550

## The Attempt at a Solution

1550÷5=310
Yes, that is correct

1550-5x310= 478950
No, 1550- 5x 310= 0, That is what $$1550÷5= 310$$ means!

Science Advisor
Yes, that is correct

No, 1550- 5x 310= 0, That is what $$1550÷5= 310$$ means!

She is using the parentheses differently (incorrectly so , by priority of operations):

1550-5=1545 , 1545x310= 474950