Can you determine the ages of Mr. P's Grandchildren from the 7 clues below?














Give the age for each of the following grandchildren:
Ben =
Carrie =
Elizabeth =
Jackson =
James =
Kate =
Stewart =


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Solution to the Problem:



Ben = 11
Carrie = 17
Elizabeth = 2
Jackson = 13
James = 19
Kate = 13
Stewart = 7

To solve the puzzle, let B= Ben's age, C = Carrie, E = Elizabeth,
X = Jackson, J = James, K = Kate, and S = Stewart.

Then you can write the following seven equations:
(1)   X + K = J + S
(2)   J = E + C
(3)   B + C = K + X + E
(4)   B + E = X
(5)   J + K = 32
(6)   B + K = S + 17
(7)   B + S + C = J + K + E + 1

Then C - E = K + E   (eq #3 - eq #4)
So, C - K = 32
K = 32 - J   (eq #5)
Then K = 32 - J
C - (32 - J) = 2E

C + J - 2E = 32
-C + J - E = 0
So, 2J - 3E = 32

Sub eq #4 in eq #1:   (B + E) + K = J + S
E + S + C = J + S>br> Then J - E = 17

So, 2J - 3E = 32
J - E = 17
-3J + 3E = -51
So, J = 19 and K = 13

Now substitute the values for J and K in the original equations:
(1)   X = S + 6
(2)   E + C = 19
(3)   B + C = X + E + 13
(4)   B + E = X
(5)   32 = 32
(6)   B = S + 4

C = 19 - E   (eq #2)
C = 2E + 13   (eq #3 - eq #4)
3E = 6, so E = 2 and then C = 17

B = S + 4   (eq #1 + eq#3)
B + S = J - 1   (eq #7)
B - S = 4
B + S = 18
2B = 22, so B = 11.   Then S = 7 and X = 13.


Correctly solved by:

1. James Alarie Flint, Michigan
2. Brijesh Dave Mumbai City, Maharashtra, India
3. McKenzie Martin Mountain View High School,
Mountain View, Wyoming
4. Bob Currie R E Campbell Company,
Houston, Texas
5. Lorenzo Quezon City, Phillipines
6. Joe Curtis Armona, California
7. Alyssa Rippetoe Mountain View High School,
Mountain View, Wyoming
8. Kaylee Gross Mountain View High School,
Mountain View, Wyoming
9. Alexis Saxton Mountain View High School,
Mountain View, Wyoming
10. Mikaela Williams Mountain View High School,
Mountain View, Wyoming