How many options do you have to choose from when you pick the first letter? How about the second letter?
C
c
There are four words you can form.
A
a
24
B
b
See solution.
C
c
1/6
Practice makes perfect
a
We should calculate 4! to determine how many arrangements there are. Start by entering 4 on your graphing calculator. Next, push MATH, scroll to the fourth menu, PRB, and choose the fourth option.
b
We start with four letters, which means the first level of our tree diagram will have four branches. Having selected the first letter, we have three letters left. Therefore, the second level of the tree diagram will have three branches, and so on. With this information we can write the following decision chart.
1 4* 2 3* 3 2* 4 1=24
Let's draw the corresponding tree diagram.
c
With the four letters, we can make the following words.
PANS
NAPS
SNAP
SPAN
To calculate the probability of a two-year-old randomly making a word, we have to divide the number of favorable outcomes with the number of possible outcomes. The number of favorable outcomes is 4 and the number of possible outcomes is 24.
P(Forms a letter)=4/24=1/6
