-31 because if you do p.e.m.d .a .s
Answer:
- not possible: 1, 2, 4, 5, 8, 11
- possible: all others
Step-by-step explanation:
Obviously, all multiples of 3 and 7 can be paid.
1 cent can be added by adding a 7-cent stamp and taking away two 3-cent stamps. 2 cents can be added by adding three 3-cent stamps and taking away one 7-cent stamp. Hence any value more than 7 +2(3) = 13 cents can always be accommodated.
Amounts that are impossible:
1, 2, 4, 5, 8, 11 cents
All other positive integer amounts are possible.
It’s bull Peter C your welcome :)
Let dimes = d and quarters =q
D + q = 50
D= 50-q
0.10d + 0.25Q = 7.70
Replace d with 50-q:
0.10(50-q) + 0.25q = 7.70
Simplify:
5 -0.10q + 0.25q = 7.70
5 + 0.15q = 7.70
Subtract 5 from both sides:
0.15q = 2.70
Divide both sides by 0.15:
Q = 2.70 / 0.15
Q = 18
D = 50-18 = 32
There are 32 dimes and 18 quarters
I say subcategory would be a good answer
