Math 7 Unit I Pre Unit Assessment

Which classification of numbers is known to be any positive number from 1 to infinity, which is also called as 'natural numbers'?

• Counting Numbers

• Integers

• Rational Numbers

• Real Numbers

Answer explanation

Counting Numbers are any positive number from 1 to infinity, also known as 'natural numbers'.

Which classification of numbers is known to be the collection of positive numbers and zero?

• Irrational Numbers

• Rational Numbers

• Real Numbers

• Whole Numbers

Answer explanation

The classification of numbers that includes positive numbers and zero is Whole Numbers.

Which classification of numbers includes fractions and decimals with repeating and non-repeating?

• Irrational Numbers

• Rational Numbers

• Real Numbers

• Whole Numbers

Answer explanation

Rational Numbers include fractions and decimals with repeating and non-repeating patterns, making it the correct classification for this scenario.

Which classification of numbers is known as the set of all positive and negative numbers which includes zero but not fractions and decimals?

• Integers

• Natural Numbers

• Rational Numbers

• Real Numbers

Answer explanation

Integers are the set of all positive and negative numbers including zero but not fractions and decimals.

Which statement is TRUE?

• All integers are whole numbers.

• All integers are rational numbers.

• All rational numbers are integers

• All real numbers are rational numbers.

Answer explanation

The statement 'All integers are rational numbers' is TRUE because integers include all whole numbers and their negatives which are classified as rational numbers too. Rational numbers consist of all whole numbers, negative numbers and non-whole numbers such as decimals and fractions. But not all rational numbers are integers because it includes non-whole numbers.

“The entrance to a silver mine is 195 meters above sea level. The mine is 102 meters deep.

How high is the entrance from the bottom of the mine.” To answer this, what step will you take?

• Subtract 102 from 195.

• Subtract 195 from 102

• Add 195 to -102

• Subtract -102 from 195

Answer explanation

To find the height of the entrance from the bottom of the mine, you need to subtract -102 (depth of the mine) from 195 (height of the entrance above sea level), which gives you the correct answer.

What is the value of the expression -10 + 3 ( 27 ÷ 3 ) ?

• -63

• 17

• -17

• 63

Answer explanation

To find the value of the expression, first solve the division inside the parentheses: 27 ÷ 3 = 9. Then, multiply 3 by 9 to get 27. Finally, add -10 from 27 to get the answer 17.

Which of the following is equal to 1?

• (-1)⁷

• (-1)¹⁵

• (-1)⁹⁸

• (-1)¹⁰¹

Answer explanation

The correct answer is (-1)⁹⁸ because it is the only option equal to 1 when considering the nature of the exponent (an even number).

The retina has 120 000 000 rods. What is this number in scientific notation?

• 1.2 × 10⁸

• 1.2 × 10⁹

• 1.2 × 10⁷

• 1.2 × 10¹⁰

Answer explanation

To express 120,000,000 in scientific notation, move the decimal point to the left until there is one non-zero digit to the left. This gives 1.2 x 10^8, so the correct choice is 1.2×10^8.

Which of the following is a finite set?

• The set of all whole numbers.

• The set of all stars in the universe

• The set of all decimal numbers in the π (pi)

• The set of counting numbers less than 10

Answer explanation

The set of counting numbers less than 10 is a finite set.

Counting numbers (or natural numbers) start from 1 and go up to any specified number.

For counting numbers less than 10, the set would be:

{1,2,3,4,5,6,7,8,9}

Since this set has a limited number of elements (specifically, 9 elements), it is a finite set.