NYS Math Grade 3 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Product

The answer to a multiplication problem. In 4 × 6 = 24, the product is 24, which equals four groups of six objects.

Unknown factor

A missing number in a multiplication sentence. In 5 × n = 35, divide to find n = 35 ÷ 5 = 7.

Commutative property

Changing the order of factors does not change the product: 3 × 7 = 7 × 3 = 21.

Distributive property

A factor can be split into parts: 8 × 6 = 8 × 5 + 8 × 1 = 40 + 8 = 48.

Division as sharing

Splitting a total into a known number of equal groups. 12 ÷ 3 means 12 objects shared into 3 groups, giving 4 in each group.

Division as measuring

Finding how many equal groups of a given size fit in a total. 12 ÷ 3 means how many groups of 3 make 12; the answer is 4.

Two-step word problem

A problem needing two operations, such as multiply then add. Example: 3 boxes of 8 markers plus 5 loose markers is 24 + 5 = 29.

Pattern rule

The operation that changes one term to the next. In 4, 8, 12, 16 the rule is add 4, so the next term is 20.

Place value

The value of a digit depends on its position. In 5,284 the 2 means 2 hundreds, or 200.

Expanded form

Writing a number as the sum of its place values: 2,706 = 2,000 + 700 + 0 + 6.

Round to nearest ten

Look at the ones digit. If it is 0-4, keep the tens digit; if 5-9, raise the tens digit by 1. 84 rounds to 80; 87 rounds to 90.

Round to nearest hundred

Look at the tens digit. If it is 0-4, keep the hundreds digit; if 5-9, raise it by 1. 1,340 rounds to 1,300; 1,380 rounds to 1,400.

Regrouping in addition

Trading 10 ones for 1 ten or 10 tens for 1 hundred. In 47 + 38, 7 + 8 = 15 ones, so write 5 and regroup 1 ten.

Regrouping in subtraction

Borrowing from the next place. In 52 - 27, borrow 1 ten so 2 ones become 12 ones, then subtract.

Estimate with compatible numbers

Replace numbers with nearby easy numbers to check an answer. 297 + 402 is about 300 + 400 = 700.

Multiply by multiples of ten

Multiply the basic fact, then attach the zero: 4 × 30 = 4 × 3 tens = 12 tens = 120.

Unit fraction

A fraction with numerator 1, such as 1/2, 1/4, or 1/8. It is one equal share of a whole.

Equivalent fractions

Different fractions naming the same amount or the same point on a number line: 1/2 = 2/4 = 4/8.

Whole number as fraction

Any whole number can be written over 1: 5 = 5/1. Also 6/3 = 2 and 8/8 = 1.

Compare same denominators

When denominators match, compare numerators. 4/9 < 7/9 because 4 is less than 7 of the same size pieces.

Compare same numerators

When numerators match, the smaller denominator is larger. 1/4 > 1/6 because fourths are bigger pieces than sixths.

Fractions on number line

Split the space from 0 to 1 into equal parts. The point at the end of the third of five parts is 3/5.

Elapsed time

The time between a start and an end. From 3:45 to 4:20: 15 minutes to 4:00 plus 20 minutes equals 35 minutes.

Telling time to minute

The minute hand moves 1 minute per small mark and 5 minutes per number. When the minute hand is on 7, 35 minutes have passed.

Liter and milliliter

Metric units of liquid volume. 1 liter = 1,000 milliliters; a small water bottle holds about 500 milliliters.

Kilogram and gram

Metric units of mass. 1 kilogram = 1,000 grams; a paper clip has a mass of about 1 gram.

Scaled picture graph

A graph where each picture stands for more than one item. If the key says 1 picture = 5 votes, 4 pictures mean 20 votes.

Area of a rectangle

Area equals length times width, counted in square units. A 6-by-4 rectangle has area 6 × 4 = 24 square units.

Perimeter of a rectangle

Perimeter is the distance around the shape: 2 × (length + width). A 6-by-4 rectangle has perimeter 2 × 10 = 20 units.

Quadrilateral

A closed shape with 4 straight sides and 4 angles. Squares, rectangles, rhombuses, trapezoids, and parallelograms are quadrilaterals.

Trapezoid

A quadrilateral with exactly one pair of parallel sides. The parallel sides are called the bases of the trapezoid.

Square as special rectangle

A square has 4 right angles and 4 equal sides, so it fits the rectangle definition too. Every square is a rectangle, but not every rectangle is a square.