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>How to compare the size of two numbers_ Primary school mathematics: the order of numbers and comparative size
Can we find a more convenient way to compare? This leads to the problem of comparing the size of two numbers represented by a counter. Use the counter to place the two numbers 39 and 45 in the left figure of example 8, and then think about how to compare them, After listening to the students' comparison method, guide the students to summarize the general method of comparing the size of two double digits: first look at the number on the ten, the number on the ten is big, the two digits are big; if the number on the ten is the same, then look at the number on the one, the number on the one is big, the two digits are big
Comparative size: 6.635 6 right 5 / 8 6 right 25 / 16 with "<" symbol link
(need to write process)
Because
Six and five eighths = 6.625
16 / 6 and 16 / 25 = 6.64
six point six two five
3 / 10 × 8 / 7 () 8 / 7
2 / 3 × 4 / 5 () 2 / 3
3 / 10 × 7 / 8（
2 / 3 × 5 / 4 () 2 / 3
3 / 10 × 8 / 7（
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