Math help asap!!

Question

1. The students in one social studies class were asked how many brothers and sisters (siblings) they each have. The dot plot here shows the results

 

a. How many of the students have six siblings? Answer:

b. How many of the students have no siblings? Answer:

 

c. How many of the students have three or more siblings? Answer:

d. What is the mean (average)? Answer:

Answer 1

The dots above a number along the horizontal axis tell you how many people have that many siblings. Just count the dots above the number of siblings along the horizontal axis.

a) 1

b) 0

c) 6 have 3 sibs, 4 have 4 sibs, 0 have 5 sibs, and 1 has 6 sibs: 6 + 4 + 0 + 1 = 11

d) We call this a frequency distribution. To compute the mean, simply multiply each sibling number by the number of people who have that number of siblings and add the products. Then divide this sum by the number of dots.

Step 1: 0*3 + 1*3 + 2*3 + 3*6 + 4*4 + 5*0 + 6*1 = 49

Step 2: 49 total siblings / 20 people surveyed = 2.45 siblings per person, on average.