Question 26523
Let the 55 cent coupon be x
Let the 30 cent coupon be 3x
Let the 50 cent coupon be x+4
Double = 2(3x)=6x
2(x+4)=2x+8
Total value = 1740
30(6x)+55x+50(2x+8)=1740
180x+55x+100x+400=1740
335x=1340
x=4

4(3)=12
4+4=8


Hence, she has 4, 55 cent coupons, 12, 30 cent coupons and 8, 50 cent coupons.
Paul.