8th Grade Math Midterm Review

The mass of a substance is 8 x 10⁹ micrograms. If one microgram is equal to 1 x 10^-6 grams, what is its mass in grams?

• 1.25 x 10^-15 grams

• 8x10³ grams

• 1.25x10^-3 grams

• 8x10¹⁵ grams

A box contains 5x10³ paper clips. The mass of each paper clip is 8x10^-4 kilograms. What is the combined mass of the paper clips in the box?

• 4 kilograms

• 4x10⁷ kilograms

• 40 kilograms

• 4x10^-7 kilograms

Divide:

(6.9 x 10⁷) / (2.3 x 10^-3)

• 3x10¹⁰

• 3x10^-4

• 3x10⁴

• 3x10^-11

Write the answer in scientific notation.

(4.1 x 10⁵ )+ (5.5 x 10⁶ )=

• 4.65 x 10⁵

• 9.6 x 10⁵

• 9.6 x 10¹¹

• 5.91 x 10⁶

Which number is largest?

• 8.4 x 10¹⁹

• 3.5 x 10³²

• 1.3 x 10³²

• 4.8 x 10^-39

Cell A = 4.2 x 10^-4

Cell B = 2.1 x 10^-5

Cell C = 8.4 x 10^-4

Cell C is ____ larger than Cell A

• 4x

• .2x

• 2x

• 20x

Which best decribes an irrational number?

• Any number that can be expresses as a fraction.

• A number that is a non-terminating, non-repeating decimal.

• A positive or negative whole number.

• The square root of any whole number.

π...rational or irrational

• rational

• irrational

Which is the best estimate of √28?

• 5.1

• 5.3

• 5.2

• 14

In between what 2 integers is the square root of 77?

• 5 and 6

• 6 and 7

• 7 and 8

• 8 and 9