Algebra 1(B) S TEM - AND -L EAF P LOTS

C HAPTER 8 W ARM -U P The population of Oswego in 2000 was 15,000. Since then, the town has experienced a 5.6% increase in population annually. How many residents can we predict there to be in Oswego today? 30,459 residents

C HAPTER 8 T EST C ORRECTIONS  Students will be placed into small groups  Corrections can be made to up to three problems to regain half-credit for each of them explanation of why your original answer was incorrect  Show your work on a separate sheet of paper along with an explanation of why your original answer was incorrect  Help each other!

O BJECTIVES  Display and interpret data on a stem-and-leaf plot

A PPLICATION OF S TEM - AND -L EAF P LOTS  Mr. Valdez wants to study the distribution of the scores for the last chapter test in Algebra 1(B). The scores of his 35 students in the class are listed below

O RGANIZING D ATA  Stem-and-leaf plots are used to display a wide range of information. stems  The greatest common place value of the data is used to form the stems. leaves  The numbers in the next greatest common place value are used to form the leaves The greatest place value is tens. Thus, the number 82 would have stem 8 and leaf 2.

T O M AKE A S TEM - AND -L EAF P LOT StemLeaf Steps: 1)Make a vertical list of stems based on the range of the values. 2)Plot each number by placing the units digit (leaf) to the right of the correct stem. Note: Note: A stem may have more than one digit. A leaf always has just one digit.

StemLeaf T O M AKE A S TEM - AND -L EAF P LOT Steps: 3) Make a new stem- and-leaf plot with the leaf values in order.

U SING THE I NFORMATION 1. What were the highest and the lowest scores? StemLeaf Which test score occurred most frequently? 3. In which 10-point interval did the most students score? 4. How many students received a score of 70 or better? 99 and (3 times) 80-89(10 students) 25 students

E X. 1: S WAGGVILLE R ESIDENTS  The following data show the ages the 25 residents of Swaggville, Illinois. Make a stem-and-leaf plot to display the data

B REAK T IME  Take a 2-3 minute break to get up, stretch out, talk to a neighbor, or try the following rebus puzzles… Shop till you dropH 2 0 (water)

M ORE T HAN T WO D IGITS  Sometimes the data for a stem-and-leaf plot are numbers that have more than two digits. stem  In this case, you may need to put more than one digit in the stem.  Noteleaf  Note : Only one digit should go in the leaf.

E X. 2: B ENCH P RESS M AX  The numbers shown below represent the maximum bench press weight of 15 high school students. Create a stem-and-leaf plot to organize the data

E X. 2: B ENCH P RESS M AX  The numbers shown below represent the maximum bench press weight of 15 high school students. Create a stem-and-leaf plot to organize the data StemLeaf Notice that the hundreds and tens place have been included in the stem.

E X. 3: W EEKLY P AYCHECK mean medianmode  The data below represents the weekly paychecks of high school students that work. Find the mean, median, and mode of the data. StemLeaf

A SSIGNMENT  pgs. 371, 373 #9, 13-16, 34  Quiz on Friday!