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Which number is greater and by how much: A decreased by 50% and then increased by 50% of the result

User Bulba
by
4.9k points

1 Answer

4 votes

Answer:

The original
A would be greater than the new value by
0.25\, A.

Explanation:

Refer to the diagram attached.


50\% of
A is equivalent to
0.5\, A.

Reducing
A by
50\% is the same as subtracting
0.5\, A from
A\!. The "result" would be
A - 0.5\, A = 0.5\, A.

Since the "result" is
0.5\, A,
50\% of the "result" would be
50\% * 0.5\, A = 0.5* 0.5\, A = 0.25\, A.

Adding
50\% of the "result" to the result itself would be the same as adding
0.25\, A to
0.5\, A, which gives the new value
0.75\, A.

Thus, the original
A would be greater than the new value by
A - 0.75\, A = 0.25\, A.

Which number is greater and by how much: A decreased by 50% and then increased by-example-1
User Dawid Loranc
by
5.0k points