Answer:
(7, 8.5)
Explanation:
Along the x-axis, the distance is 9 - 1 = 8
Along the y-axis, the distance is 11 - 1 = 10
Since Anna travels 3 times as fast as Mary, she travels 3 times as much distance. Anna's distance is AC while Mary's distance is CB.
AC:CB = 3:1.
C is 3/(3+1) = 3/4 of AB.
Hence, the coordinate of C is
(1 + 3/4 × 8, 1 + 3/4 × 10) = (1 + 6, 1 + 7.5) = (7, 8.5)
1 is added to the components of the coordinate because A is at (1, 1).