Represent as
w=wally
a=ashan
so wally has 2 more marbles than ashan
w=2+a
together they have 88
w+a=88
since w=2+a, subsitute (2+a) for w in the w+a=88 equation
2+a+a=88
add like terms
2+2a=88
subtract 2 from both sides
2a=86
divide by 2
a=43
ashan has 43 marbles
For the scale factor, use the dimensions from similar sides:
Using 18 from the original image you would use 6 from the scaled image.
18 /6 = 3
This means the scaled image is 3 times smaller than the original. Because the scaled image is smaller divide 1 by the scale factor to get 1/3.
Q2:
The scale factor is 1 inch = 12 miles.
Multiply the total inches by 12:
6.5 x 12 = 78 miles.