Today’s math tip is applicable across all levels as this kind of question have been getting more and more popular over the years!

Using “Rainbow method” known as Gauss Method by a famous Mathematician (Carl Friedrich Gauss), pair the numbers in sequence.

**Basic: What is the sum of 1 to 10?**

1+2+3+4+5+6+7+8+9+10 = ?

Pair the following numbers eg:

1 + 10 = 11

2 + 9 = 11

3 + 8 = 11

4 + 7 = 11

5 + 6 = 11

There, you have 5 pairs of (11) = 5 x 11 = 55

Therefore,

1 + 10 = 11 (Sum of a pair)

10 ÷ 2 = 5 (divided by 2 as each set consist of 2 numbers)

5 x 11 = 55

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**Advanced Question: What is the sum of 1 to 100?**

1 + 2 + 3 + 4 + … + 98 + 99 + 100 = ?

1 + 100 = 1012 + 99 = 1013 + 98 = 101…48 + 53 = 10149 + 52 = 10150 + 51 = 101

Solution:

1 + 100 = 101

100 ÷ 2 = 50 (there are 50 sets of 101)

50 x 101 = 5050

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**Advanced Question: What is the sum of 1 to 59?**

1 + 2 + 3 + 4 + … + 98 + 99 = ?

Solution:

1 + 59 = 60

59 ÷ 2 = 29.5

29.5 x 60 = 1770

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