6/10, 9/10, 12/10 or 1 1/2, and 15/10 or 1 1/2
j = # of jars
b = # of buckets
y = total # of rocks
2j + 3b = y (2 rocks per jar, 3 rocks per bucket)
Because Joy has 3 jars you can plug 3 in for "j", and because she has 4 buckets you can plug in 4 for "b"
2(3) + 3(4) = y
6 + 12 = y
18 = y
X+y=12 -- 1
3x+2y=29 -- 2
(1)x2
2x+2y=24 -- 1
(2)-(1)
x=5
Sub x into 1
x+y=12
5+y=12
y=7
Her two numbers are 5 and 7
Janes weight = x
Twelve pounds less than twice janes weight is 270 pounds
12 less than 2x is 270
2x -12 = 270 (add 12 to each side)
2x = 270 + 12
2x = 282 (divide 2 from each side)
x = 282/2
x = 141
The answer is 141 pounds