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Zarrin [17]
3 years ago
13

When 2/3 of a number is increased by 20, the sum is then halved, the result obtained is the same as 2/3 of the number, increased

by 3. Find the number.
Mathematics
1 answer:
aleksklad [387]3 years ago
4 0

\frac{2/3x+20}{2} =\frac{2}{3} x+3\\\frac{2/3x+20}{2} - 3 = \frac{2}{3}x\\\frac{2/3x+20}{2} - \frac{6}{2} = \frac{2}{3}x\\\frac{2/3x+20-6}{2} = \frac{2}{3}x\\\frac{2/3x+14}{2} = \frac{2}{3}x\\2(\frac{2/3x+14}{2}) = 2(\frac{2}{3}x)\\2/3x+14=\frac{4}{3}x\\14=\frac{4}{3}x-\frac{2}{3}x\\14=\frac{2}{3}x\\\frac{14}{1}/\frac{2}{3}=x\\\frac{14}{1}*\frac{3}{2}=x\\7*3=x\\x=21

The number is 21.

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) See annex

b) See annex

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