Basic Multiplication

Question 1

Multiply by 11

Answer 1

C + N

Question 2

Multiply by 12

Answer 2

2C + N

Question 3

Multiply by 5

Answer 3

hN (+5ifo)

Question 4

Multiply by 6

Answer 4

C + hN +5ifo

Question 5

Multiply by 7

Answer 5

2C + hN + 5ifo

Question 6

Multiply by 9

Answer 6

1) 10-C
2) (9-C)+N
3) N-1

Question 7

Multiply by 8

Answer 7

1) 2(10-C)
2) 2(9-C)+N
3) N-2

Question 8

Multiply by 4

Answer 8

1) (10-C)+5ifo
2) (9-C)+hN+5ifo
3) hN-1

Question 9

Multiply by 3

Answer 9

1) 2(10-C)+5ifo
2) 2(9-C)+hN+5ifo
3) hN-2