MCAS Math Grade 4 key terms

The value a digit has because of its position in a number. In 4,582 the 5 means 5 hundreds, or 500, while the 8 means 8 tens, or 80.

A number written with digits only, using place value positions, such as 3,407. This is the usual way numbers appear in problems and on answer sheets.

A number broken apart to show the value of each digit, written as a sum. For example, 3,407 is written as 3,000 + 400 + 7.

A number written out in words, such as three thousand four hundred seven. Hyphens and commas are usually left out, and the word and is not needed.

Replacing a number with a nearby number of a chosen place value. Look at the digit to the right: 4 or less keeps the digit, 5 or more increases it by one.

A number close to an exact answer, found by rounding or using friendly numbers. Estimates help check whether a calculated answer is reasonable.

Numbers adjusted to make mental arithmetic easier, such as changing 397 + 48 to 400 + 48. They give an estimate rather than an exact answer.

To decide which of two numbers is greater or whether they are equal, using the symbols >, <, and =. Compare place values from left to right.

To arrange numbers from least to greatest or greatest to least. Comparing digits place by place, starting at the left, determines the order.

The result of adding two or more numbers together. In 245 + 138 = 383, the sum is 383.

The result of subtracting one number from another. In 500 - 176 = 324, the difference is 324.

The result of multiplying two or more numbers. In 6 × 7 = 42, the product is 42.

The result of dividing one number by another. In 56 ÷ 8 = 7, the quotient is 7.

A number that is multiplied in a multiplication expression, or a number that divides another evenly. In 4 × 9 = 36, both 4 and 9 are factors.

The result of multiplying a whole number by another whole number. Multiples of 6 include 6, 12, 18, 24, and so on.

The number being divided in a division problem. In 72 ÷ 9 = 8, the dividend is 72.

The number you divide by in a division problem. In 72 ÷ 9 = 8, the divisor is 9.

The amount left over when a number does not divide evenly. Dividing 25 by 4 gives a quotient of 6 with a remainder of 1.

A whole number greater than 1 with exactly two factors, 1 and itself. Examples are 2, 3, 5, 7, and 11.

A whole number greater than 1 that has more than two factors. For example, 12 has the factors 1, 2, 3, 4, 6, and 12.

A number that names part of a whole or part of a set, written as a numerator over a denominator. The denominator tells how many equal parts there are.

The top number of a fraction. It tells how many equal parts are being described, as in 3/4, where 3 is the numerator.

The bottom number of a fraction. It tells the total number of equal parts in the whole, as in 3/4, where 4 is the denominator.

Fractions that name the same amount even though the numbers differ, such as 1/2 and 2/4. Multiplying numerator and denominator by the same number creates them.

A number written with a decimal point to show whole-number parts and parts less than one. In 3.75, the 7 stands for seven tenths.

The dot that separates the whole-number part from the fractional part of a decimal. Digits to its right have place values of tenths, hundredths, and so on.

The number of square units needed to cover a flat figure. A rectangle's area equals length times width.

The distance around the outside of a closed figure, found by adding the lengths of all its sides. Perimeter is measured in linear units such as inches or centimeters.

A square with sides one unit long, used to measure area. A rectangle 3 units by 4 units covers 12 square units.

A figure formed by two rays that share a common endpoint called the vertex. Angles are measured in degrees with a tool called a protractor.

An angle that measures exactly 90 degrees, often shown with a small square mark. The corners of a rectangle and a square are right angles.

The unit used to measure angles. A full turn is 360 degrees, a straight angle is 180 degrees, and a right angle is 90 degrees.

A line that divides a figure into two matching halves that fold onto each other exactly. A square has four lines of symmetry.

Having exactly the same size and shape. Two figures are congruent if one can be moved onto the other and match perfectly.

A sequence or arrangement that follows a repeating or growing rule. For example, 3, 6, 12, 24 doubles each time.

The operation or relationship that generates each term of a pattern from the one before. For example, the rule add 5 turns 2 into 7.

A number line marked with data values where each X above a value stands for one observation. It shows how often each value occurs.

The value that appears most often in a data set. A set can have one mode, more than one mode, or no mode.

The middle value of a data set arranged in order. If there are two middle values, the median is their average.

A number made of a whole number and a fraction, such as 2 1/3. It can be rewritten as an improper fraction.

A fraction whose numerator is greater than or equal to its denominator, such as 7/4. Its value is 1 or more.