You are at your best friend's family reunion, and all of the relatives are reminiscing about their childhood. Look at the pictures and tell what everyone did as children. Follow the model. Modelo: ¿Qué hacía el abuelito? El abuelito pescaba con su padre. ¿Qué hacían los tíos? _____

In a family with $2$ children, the probability that both children will be boys is $1/4$. Suppose $1200$ families with two children are selected at random.

(a) How many of the families would we expect to have $2$ boys?

(b) What is the standard deviation of the number of families with $2$ boys?

( c ) Suppose that of the $1200$ families, $315$ families have two boys. How many standard deviations above the mean is this number ( $315$ ) of families?

In a first-grade class the teacher gave the following problem: There are 12 boys and 8 girls. How many more boys than girls? A majority of the children answered "four more boys" correctly, but 5 children chose to add and gave "20 children" as their answer. One of these 5 children insisted that subtraction could not be used because it is impossible to take away 8 girls from 12 boys. None of the other children could respond to this child's claim. In light of what you have learned in this section, describe how you would handle this situation if you were the teacher, in order to help this child understand that subtraction is the appropriate operation in this situation. Note that simply telling a student "the right way" does not necessarily help him or her understand.

Two children are holding a rope taut between them when one suddenly yanks the rope. (a) Does the child at the other end instantly get pulled? (b) Answer the same question for two children holding a rigid steel bar between them.

You are at your best friend's family reunion, and all of the relatives are reminiscing about their childhood. Look at the picture and tell what everyone did as children. Follow the model.

Modelo: ¿Qué hacía el abuelito? - El abuelito pescaba con su padre.

¿Qué hacía el padre?

Can eating nuts during pregnancy help children avoid nut allergies? Researchers studied over 8000 children who were born in the early 1990s to mothers who were part of the Nurses' Health Study II. Children whose mothers ate the most nuts during pregnancy (at least 5 times per week) were significantly less likely to develop nut allergies than children whose mothers ate the least amount of nuts during pregnancy (less than once per month).

What is the largest population to which we can generalize these results?

Decide which form of the vocabulary word in parentheses best completes the sentence. The form given may be correct. Write your answer on the answer line.

Because the Sullivans expect their children to help out, they do not $\underline{?}$ the children for cleaning their rooms. (laudable) _____________________

The weights of two children sitting at ends A and B of a 12-ft seesaw are 72 lb and 52 lb, respectively. Determine the position of a third child so that the resultant of the weights of the three children will pass through the center C if she weighs 54 lb.

The percentage of families that were married couples with children between 1970 and 2010 is approximately $P(t)=\frac{49.6}{t^{0.27}} \ (1 \leq t \leq 5)$ where t is measured in decades, with t = 1 corresponding to 1970. a. What percentage of families were married couples with children in 1970? In 1990? In 2010? b. How fast was the percentage of families that were married couples with children changing in 1990? In 2000?

You are at your best friend's family reunion, and all of the relatives are reminiscing about their childhood. Look at the pictures and tell what everyone did as children. Follow the model. Modelo: ¿Qué hacía el abuelito? El abuelito pescaba con su padre. ¿Qué hacían tú y tu abuela? _____

A man bought three vanilla ice cream cones, two chocolate cones, four strawberry cones, and five butterscotch cones for his 14 children. In how many ways can he distribute the cones among his children?

When the class was asked to pose a meaningful problem that corresponded to the division 14 divided by 3, Peter’s problem was answered by 4, Tina’s by 5, and Andrea’s by 4 with a remainder of $2$. Carefully explain how all three children may be correct by posing three problems of your own that give their answers.

You are at your best friend's family reunion, and all of the relatives are reminiscing about their childhood. Look at the pictures and tell what everyone did as children. Follow the model. Modelo: ¿Qué hacía el abuelito? El abuelito pescaba con su padre. ¿Qué hacía la tía Ramona?

A woman decides to have children until she has her first girl or until she has four children, whichever comes first. Let X = number of children she has. For simplicity, assume that the probability of a girl is .5 for each birth. Write the simple events in the sample space. Use B for boy and G for girl. For instance, one simple event is BG, because the woman would stop having children once she has a girl. Find the probability for each of the simple events in the sample space. Find the probability distribution function for X. Draw a picture of the probability distribution function for X.