Question

If $A = \{1, 3, 5, 7\}$ and $B = \{1, 2, 3, 4, 5, 6, 7, 8\}$, then the number of one-to-one functions from $A$ into $B$ is:}

• A. \( 1340 \)
• B. \( 1860 \)
• C. \( 1430 \)
• D. \( 1880 \)
• E. \( 1680 \)

Hint:

For 1-1 functions, think of it as "picking" a partner for each element of A from B without replacement. The first element of A has 8 choices, the second has 7, the third has 6, and the fourth has 5.

Answer 1

Answer: (E)