Answer:
300 dollars
Step-by-step explanation:
Let the original amount = x
x - 2/5x was what his mother's share looked.
5/5 x - 2/5 x
3/5x is what is left.
3/5 x - 1/4 * 3/5 x - 2/3x * 3/5 = his sister's share and his brothers
3/5x - 1/4*3/5 x - 2/3 * 3/5 = 15
3/5x * (1 - 1/4 - 2/3) = 15
3/5 x 5/60 = 15
15 / 300 * x = 15
1/20 x = 15
x = 15 * 20
x = 300
A is the mid point ==> AL = AB = 2AB
6x-17=2(2x+3) => 6x -17 = 4x +6 => 2x = 23 =>x=23/2
then just plug x into LB and AB
I would suggest looking up a converter chart, I don't know all of them but I can help with some.
For yards to feet you have to divide by 3 because there are 3 feet in a yard.
For lbs, it's 16 oz in a pound, so divide by 16.
For miles to yards you divide by 1760 because there are 1760 yards in a mile.
I hope this helps a little bit.