Lesson 13: Practice Problems

Problem 1

Evaluate each expression. Use scientific notation to express your answer.

$(1.5 \times 10^{2}) (5 \times 10^{10})$
$\frac{4.8 \times 10^{- 8}}{3 \times 10^{- 3}}$
$(5 \times 10^{8}) (4 \times 10^{3})$
$(7.2 \times 10^{3}) \div (1.2 \times 10^{5})$

Problem 2

How many bucketloads would it take to bucket out the world’s oceans? Write your answer in scientific notation.

Some useful information:

The world’s oceans hold roughly $1.4 \times 10^{9}$ cubic kilometers of water.
A typical bucket holds roughly 20,000 cubic centimeters of water.
There are $10^{15}$ cubic centimeters in a cubic kilometer.

Problem 3 From Unit 6 Lesson 5

The graph represents the closing price per share of stock for a company each day for 28 days.

A graph with a scale of 0 to 28 (x) and 0 to 80 (y). The line has many segments and rises and falls.

What variable is represented on the horizontal axis?
In the first week, was the stock price generally increasing or decreasing?
During which period did the closing price of the stock decrease for at least 3 days in a row?

Problem 4

Write an equation for the line that passes through $(- 8.5, 11)$ and $(5, - 2.5)$ .

Problem 5

The point $(- 3, 6)$ is on a line with a slope of 4.

Find two more points on the line.
Write an equation for the line.

Problem 6 From Unit 2 Lesson 11

Explain why triangle $A B C$ is similar to triangle $C F E$ .

a. Triangle A (0,0) B (1,0) C (1,2) and larger triangle C (1,2) E (3, 6) F (3,2) with a line running through (0,0) through their hypotenuse's.

Problem 7 From Unit 6 Lesson 8

Two students join a puzzle solving club and get faster at finishing the puzzles as they get more practice. Student A improves their times faster than Student B.

Label the lines $ℓ$ and $m$ with the matching student.
Which student was faster at puzzle solving before practice?