<PRE><B>Question 463455</B>
Let M = age of Mary
    C = age of Cora

1st equation:
M-7 = 6(C-7)
M-7 = 6C-42
2nd equation:
M+1 = 2(C+1)
M+1 = 2C+2

Subtract the 1st equation by 2nd equation to eliminate M
-7-1 = 6C-42-2c-2
-8+44 = 4C
4C = 36
C = 9

Substitute C = 9 in 2nd equation to get
M+1 = 2*9 +2
M = 19

Mary is 19 years old.
Cora is 9 years old.</PRE>