We can use partial products model to solve 6×17
here Multiplicand =6
Multiplier=17
First break Multiplier (17) into 1 ten and 7 ones as
17=10+7
Then Multiply 6 to both of the parts of 17 then add it,
6×17
=6(10+7)
=6×10+6×7 [Distributive property]
=60+42=102
Partial Product is a product obtained by multiplying the multiplicand by one digit of the multiplier when the multiplier has more than one digit.
Answer:

Step-by-step explanation:
Here first open the inner parentheses and use the distributive property,

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.
The number is 18
hope this helps