=\(\frac{631}{315}.\frac{1}{651}-\frac{1}{105}.\frac{2603}{651}-\frac{4}{315.651}+\frac{4}{105}\)
=\(\frac{631}{315.651}-\frac{2603}{105.651}-\frac{4}{315.651}+\frac{4}{105}\)
=\(\frac{631}{315.651}-\frac{4}{315.651}-\frac{2603}{105.651}+\frac{4}{105}\)
=\(\frac{631-4}{315.651}-\frac{2603}{105.651}+\frac{4}{105}\)
=\(\frac{627}{315.651}-\frac{2603}{105.651}+\frac{4}{105}\)
=\(\frac{627}{105.3.651}-\frac{2603}{105.651}+\frac{4}{105}\)
=\(\frac{627}{105.3.651}-\frac{2603.3}{105.3.651}+\frac{4.651.3}{105.3.651}\)
=\(\frac{627-7809+7812}{205065}\)
=\(\frac{630}{205065}\)
=\(\frac{2}{651}\)
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