Question

Plant Types: A B C D E
Number of Seedlings: 100 140 80 60 40
A farmer conducted an inventory on his two square kilometers of rainforest; the results are in the table. He plans on randomly selecting a seedling to experiment on when he goes back to the forest. What is the probability that he will randomly pick a type B
plant? Write your answer in the simplest form of a fraction.

Answer 1

To find the probability of randomly picking a type B plant, we first need to determine the total number of seedlings.

The total number of seedlings can be calculated by adding the number of seedlings of each type:

- Type A: 100
- Type B: 140
- Type C: 80
- Type D: 60
- Type E: 40

Now, we sum these values:

\[
100 + 140 + 80 + 60 + 40 = 420
\]

Now, to find the probability of picking a type B plant, we take the number of type B seedlings (which is 140) and divide it by the total number of seedlings (420):

\[
\text{Probability of type B} = \frac{\text{Number of type B seedlings}}{\text{Total number of seedlings}} = \frac{140}{420}
\]

Next, we simplify this fraction. Both 140 and 420 can be divided by their greatest common divisor, which is 140:

\[
\frac{140 \div 140}{420 \div 140} = \frac{1}{3}
\]

Thus, the probability that the farmer will randomly pick a type B plant is:

\[
\boxed{\frac{1}{3}}
\]