A researcher wanted to know which type of toy 3-year-olds prefer for play. The researcher placed a tricycle, blocks, a train set, and puzzles in a room and observed how many of 20 children played with each type of toy. What is the k value for this study

k = 4

Step-by-step explanation:

The formula for binomial probability distribution is;

P(X = k) = C(n, k) × p^(k) × (1 - p)^(n - k)

Where C(n, k) is the number of possible ways that n number of people choose k.

While p is probability of success

In this question, 20 children want to choose from 4 toys namely tricycle, blocks, a train set, and puzzles.

This means that from binomial probability distribution formula, n = 20 and k = 4.

Step-by-step explanation:

4u-4u+8w= -3u-4u+2w

8w-2w= -7u+2w-2w

6w= -5u

w= (-5u/6)