Just because they are born the same year doesn’t mean the sister isn’t older or “bigger”. They could have an 11 months difference and have the same age for 1 month each year. You should be able to do it with these hints. I can’t give you anymore hints so here’s the answer using the hints:
*ANSWER SPOILER*
a. “Move two years from the brother’s age, and the difference in age becomes four years”
The difference in age is 4 AND the sister’s age would be two times that of the brother’s: This only works with 4 and 8.
b. “Move three years, and the difference becomes six years makes her three times as old”
The difference in age is 6 AND the sister’s age would be three times that of the brother’s: This only works with numbers 3 and 9.
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use simultaneous equation, but the answer actually surprise me!!
Comment by sspider April 21, 2008 @ 7:50 amJust because they are born the same year doesn’t mean the sister isn’t older or “bigger”. They could have an 11 months difference and have the same age for 1 month each year. You should be able to do it with these hints. I can’t give you anymore hints so here’s the answer using the hints:
*ANSWER SPOILER*
a. “Move two years from the brother’s age, and the difference in age becomes four years”
The difference in age is 4 AND the sister’s age would be two times that of the brother’s: This only works with 4 and 8.
b. “Move three years, and the difference becomes six years makes her three times as old”
The difference in age is 6 AND the sister’s age would be three times that of the brother’s: This only works with numbers 3 and 9.
c. “They were born the same year.”
They are both 6 years old.
Comment by Nawaf September 16, 2008 @ 1:41 am