Test prep
steel is a mixture of iron, carbon, and other elements. the table shows the
number of parts of each element in two different-sized samples of steel.
other elements
iron
carbon
7
90
sample # 1
sample # 2
3.5
45
1.5
a. what is the unit rate of parts iron to parts carbon?
pic
- 30
b. what is the unit rate of parts iron to parts all other elements, including
carbon?

An annual marathon covers a route that has a distance of approximately 26 miles. winning times for this marathon are all over 2 hours. the following data are the minutes over 2 hours for the winning male runners over two periods of 20 years each. earlier period 14 12 15 22 13 10 19 13 9 14 20 18 16 20 23 12 18 17 6 13 recent period 7 11 7 14 8 9 11 14 8 7 9 8 7 9 9 9 9 8 10 8 (a) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the earlier period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks. for more details, view how to split a stem.) minutes beyond 2 hours earlier period 0 1 2 (b) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the recent period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks.) minutes beyond 2 hours recent period (c) compare the two distributions. how many times under 15 minutes are in each distribution

Write a similarity statement for the similar triangles. afgh ~ a

The seventh-grade students at charleston middle school are choosing one girl and one boy for student council. their choices for girls are michaela (m), candice (c), and raven (r), and for boys, neil (n), barney (b), and ted (t). the sample space for the combined selection is represented in the table. complete the table and the sentence beneath it.