Test 2 7 Acc Study guide

​Test 2 Study Guide
7th ACC

By LMS Math 7

Scientific Notation

Tip!
Your decimal point should always be after the first natural number.

Match

Match the following

• $$4.89\cdot10^{-3}$$

• $$4.89\cdot10^2$$

• $$4.89\cdot10^{-6}$$

• $$4.89\cdot10^4$$

0.00489

489

0.00000489

4,890

• 0.00489

• 489

• 0.00000489

• 4,890

Math Response

The length of a tiny bacteria observed under a microscope is 0.0000417 millimeters. What is the value of the exponent of the length when it is written in scientific notation?

Type answer here

Correct Answer: -5

Deg^°

Rad

Multiple Choice

The distance between two planets in a solar system is 1,283,500 kilometers. What is the distance written in scientific notation?

• 1.2835 x 10^6
• 1.2835 x 10^7
• 1.2835 x 10^5
• 1.2835 x 10^4

Word Problems from Equations/Inequalities

Think of it like a story and look for your key words! per and each usually mean to multiply.
Use your key words to determine equation or inequality!

= (Equal, Same as, Is)

Multiple Choice

A storage silo contains 2,400 pounds of grain. The silo loses 45 pounds of grain every hour due to pests. At the same time, a different silo is being filled with grain at a rate of 320 pounds per hour.

Which inequality represents all possible values of x, the number of hours that have passed when the first silo contains less grain than the second silo?

• 2400−45x<320x

• 2400−320x<45x

• 2400−45x>320x

• 2400+45x<320x

Multiple Choice

Liam and Maya are saving money for a new laptop. Liam has $180 saved and plans to save $40 a week. Maya has $220 saved and plans to save $60 a week. Write an equation that can be used to determine x, the number of weeks it will take Liam and Maya to have the same amount of money saved.

• 180+40x=220+60x

• 180+60x=220+40x

• 220+40x=180+60x

• 220+60x=180+40x

Multiple Choice

Which situation can be represented by this equation?
5x+4=9x

• Alex jogs at 5 miles per hour, but he starts 4 miles ahead of Sam. Sam jogs at 9 miles per hour from the starting line. What is x, the number of hours they jog until they have covered the same distance?

• Alex earns 5 points per hour in a game. Sam earns 9 points per hour. Alex started with 4 points less than Sam. What is x, the number of hours they play to have the same score?

• Sam skates at 5 miles per hour starting 4 miles behind Alex, who skates at 9 miles per hour from the start. What is x, the time when they have traveled the same distance?

• Alex rents a bike for $5 per hour. Sam rents a bike for $9 per hour plus a $4 fee. What is x, the number of hours the cost is the same?

Multiple Choice

A coffee shop sells cups of coffee for xxx dollars each. Which situation can be represented by this inequality?

7x>4x+57

• The cost of 7 cups of coffee is greater than the cost of 4 cups plus a $5 tip.

• The cost of 7 cups of coffee is less than the cost of 4 cups with a $5 discount.

• The cost of 7 cups of coffee is equal to the cost of 4 cups plus $5.

• The cost of 7 cups of coffee is greater than the cost of 4 cups with a $5 discount.

Math Response

Solve for x:

6x+14−4x=5x−10

Type answer here

Correct Answer: 8

Deg^°

Rad

Math Response

Solve for x:

8x+18−5x=6x+9

Type answer here

Correct Answer: 3

Deg^°

Rad

Math Response

Solve for x:

5x−4=−x+8

Type answer here

Correct Answer: 2

Deg^°

Rad

Math Response

Solve for x:

4x+7=−2x+19

Type answer here

Correct Answer: 2

Deg^°

Rad

Math Response

Solve for x:

2x+4x−6+2(x+4)=4x+10

Type answer here

Correct Answer: 2

Deg^°

Rad