The scores of each group were compared between 2 / 15 and 14 / 17

Fourteen out of seventeen are more than two out of fifteen

When 4 / a = 9 / b = 2 / 5, a is (), B is ()

When 4 / a = 9 / b = 2 / 5, a is (10), B is (45 / 2)
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A: The ratio of B = two fifths, (a ／ four fifths): (b ／ four fifths) is () according to ()

a: B = 2:5, so the first empty is two fifths
According to the same number divided by (or multiplied by) the same number at the same time, the ratio remains unchanged

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