Darren's answer to Xeno's Primary 6 Maths Algebra Singapore question.
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Group the first and last number
Date Posted:
4 years ago
How do you know there is 25 sets of even numbers and 20 sets of odd numbers?
Simple. Because you paired them.
1 pair = 2
So for 50 numbers to be grouped into pairs,
50 ÷ 2 = 25 pairs.
Each pair has the same total value.
Same logic goes for the 40 odd numbers
So for 50 numbers to be grouped into pairs,
50 ÷ 2 = 25 pairs.
Each pair has the same total value.
Same logic goes for the 40 odd numbers
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