Both x and y vary inversely with each other. When x is 10, y is 6, which of the following is not a possible pair of corresponding values of x and y?
Since x and y vary inversely, i.e. 
If x = 10 and y = 6
∴ 
In option (a), 
In option (b), 
In option (c), 25× 2.4 = 60
In option (d), 45 × 1.3 = 58.3
Hence option (d) is correct.
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