Posted by becky on Monday, May 9, 2011 at 7:13am.
My mother and I are the same age – only the numbers are reversed (21,12 for example)
Twelve years ago my mom was twice as old as me.
So how old is my mommy and how old am I?
- math - drwls, Monday, May 9, 2011 at 8:25am
Let the two digits in the ages be x and y. Your mother's age now is 10x + y. Yours is 10 y + x.
Twelve years ago,
10 x + y -12 = 2 (10 y +x-12)
10 x + y = 20y + 2x -12
19y = 8x + 12
Try integers 0 through 9 for y and see which gives an integer for x.
Only this combination works:
y = 4, x = 8
Current ages are 48 and 84.
Twelve years ago they were 36 and 72
- math - Reiny, Monday, May 9, 2011 at 8:27am
mom's age -- 10x + y
daughter ---- 10y + x
10x + y -12 = 2(10y +x - 12)
8x -19y = -12
now both x and y are probably integers, and y has to be less than x
I tried y = 1,2,3,4 and
y = 4 worked
when y = 4, x = 8
so mom is now 84 and the daughter is 48
12 years ago mom was 72
and the daughter was 36 , check!
Answer This Question
More Related Questions
- math - A. Brad is 12 years older than Sam . If Brad were 8 years older than he ...
- math - A. John is now 10 years older than Marcus. Three times John's age 5 years...
- Math - Sean's mom was 27 years old when he was born. When Sean is 14 years old ...
- Math - how do you solve? kim's mom is 47 years old. in 5 years her mother will ...
- Math - Gabriella is x years old.Her sister Felicia,is six years old than she is....
- math - Jack is twice as old as he was 5 years ago. His mother was then six times...
- Math - 2x represents that Clyde is twice (2 times) as old as Bonnie. 6 years ...
- math - A. A woman was 30 years old when her daughter was born.Her age is now 6 ...
- Math - age problem - One year ago Liz was 3 times as old as her brother Jack. In...
- math - 1. Lisa is 15 years old and her father is 40. How many years ago was the ...