Number and Quantity Review

The table shows four quantities.

Each quantity is assigned a numeric label.

Order the quantities from least to greatest.

The approximate volume of an average bacterium is 3 x 10^-19 cubic meters. Abigail calculates the volume of 10,000 bacteria. She plans to multiply 10,000 by 3 x 10^-19 and use scientific notation to record the answer.

If Abigail calculates correctly, what is the value of n?

What is the value of x in the equation shown below?

0.25x + 7 = 4(x – 2)

Use the Desmos graphing calculator.

Four times the sum of a number r and 4 is equal to 20 less than 10 times the number r. What is the value of r? Note: Create the equation. Use Desmos to solve by replacing "r" with "x."

What did Martina do to get 2x = 402?

• divided both sides by 2

• divided the left side by 2x

• subtracted 2x from both sides

• subtracted 2x from the left side and added 2x to the right side

What are the numbers of round and oval beads Kelsey purchased?

• 1 round bead, 4 oval beads

• 2 round beads, 3 oval beads

• 4 round beads, 1 oval bead

• 5 round beads, 1 oval bead

A car rental company charges $34 per day for a rented car and $0.50 for every mile driven. A second car rental company charges $20 per day and $0.75 for every mile driven. What is the number of miles at which both companies charge the same amount for a one-day rental?

• 56 miles

• 54 miles

• 36 miles

• 24 miles

Place the correct value to complete the sentence.

At the Quartz Farm there are 1/4 as many lemon trees as orange trees. There are a total of 90 trees on the farm.

There are ​ (a)   lemon trees on the farm.

• 18

• 5

• 22

• 72

• 360

What is the value of x?

• 11 and 12

• 9 and 10

• 7 and 8

• 5 and 6