# Fraction Standards – Grades 3-7

## THIRD GRADE 3.NF Number and Operation: Fractions

### FOURTH GRADE 4.NF Number and Operations | Fractions

#### Understand decimal notation for fractions, and compare decimal fractions.

5. Express a fraction with denominator 10 as an equivalent fraction with denominator
100, and use this technique to add two fractions with respective denominators 10 and
100.4 For example, express 3=10 as 30=100, and add 3=10 + 4=100 = 34=100.
6. Use decimal notation for fractions with denominators 10 or 100. For example,
rewrite 0:62 as 62=100; describe a length as 0:62 meters; locate 0:62 on a number line
diagram.
7. Compare two decimals to hundredths by reasoning about their size. Recognize that
comparisons are valid only when the two decimals refer to the same whole. Record the
results of comparisons with the symbols >;=, or <, and justify the conclusions, e.g., by using a visual model
4Students who can generate equivalent fractions can develop strategies for adding fractions with
unlike denominators in general. But addition and subtraction with un-like denominators in general
is not a requirement at this grade.

##### Use equivalent fractions as a strategy to add and subtract fractions.

1. Add and subtract fractions with unlike denominators (including mixed numbers) by
replacing given fractions with equivalent fractions in such a way as to produce an equiv-
alent sum or di erence of fractions with like denominators. For example, 2=3 + 5=4 =
8=12 + 15=12 = 23=12. (In general, a=b + c=d = (ad + bc)=bd.)
2. Solve word problems involving addition and subtraction of fractions referring to the
same whole, including cases of unlike denominators, e.g., by using visual fraction models
or equations to represent the problem. Use benchmark fractions and number sense of
fractions to estimate mentally and assess the reasonableness of answers. For example,
recognize an incorrect result 2=5 + 1=2 = 3=7, by observing that 3=7 < 1=2.

##### Perform operations with multi-digit whole numbers and with decimals to hundredths.

7. Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the re-
lationship between addition and subtraction; relate the strategy to a written method and
explain the reasoning used.
Apply and extend previous understandings of multiplication and division to
multiply and divide fractions.
3. Interpret a fraction as division of the numerator by the denominator (a=b = ab).
Solve word problems involving division of whole numbers leading to answers in the form of
fractions or mixed numbers, e.g., by using visual fraction models or equations to represent
the problem. For example, interpret 3/4 as the result of dividing 3 by 4, noting that 3=4
multiplied by 4 equals 3, and that when 3 wholes are shared equally among 4 people each

person has a share of size 3=4. If 9 people want to share a 50-pound sack of rice equally
by weight, how many pounds of rice should each person get? Between what two whole
4. Apply and extend previous understandings of multiplication to multiply a fraction
or whole number by a fraction.
a. Interpret the product (a=b)  q as a parts of a partition of q into b equal parts;
equivalently, as the result of a sequence of operations aqb. For example, use a visual
fraction model to show (2=3)4 = 8=3, and create a story context for this equation. Do
the same with (2=3)  (4=5) = 8=15. (In general, (a=b)  (c=d) = ac=bd.)
b. Find the area of a rectangle with fractional side lengths by tiling it with unit
rectangles6 of the appropriate unit fraction side lengths, and show that the area is the
same as would be found by multiplying the side lengths. Multiply fractional side lengths
to nd areas of rectangles, and represent fraction products as rectangular areas.
5. Interpret multiplication as scaling (resizing), by:
a. Comparing the size of a product to the size of one factor on the basis of the size
of the other factor, without performing the indicated multiplication.
b. Explaining why multiplying a given number by a fraction greater than 1 results
in a product greater than the given number (recognizing multiplication by whole num-
bers greater than 1 as a familiar case); explaining why multiplying a given number by a
fraction less than 1 results in a product smaller than the given number; and relating the
principle of fraction equivalence a=b = (na)=(nb) to the e ect of multiplying a=b by 1.
6. Solve real world problems involving multiplication of fractions and mixed numbers,
e.g., by using visual fraction models or equations to represent the problem.
7. Apply and extend previous understandings of division to divide unit fractions by
whole numbers and whole numbers by unit fractions.7
a. Interpret division of a unit fraction by a non-zero whole number, and compute
6In the original, it is incorrectly stated as \squares”.
7Students able to multiply fractions in general can develop strategies to divide fractions in general,
by reasoning about the relationship between multiplication and division. But division of a fraction
by a fraction is not a requirement at this grade.

such quotients. For example, create a story context for (1=3)4, and use a visual fraction
model to show the quotient. Use the relationship between multiplication and division to
explain that (1=3)  4 = 1=12 because (1=12)  4 = 1=3.
b. Interpret division of a whole number by a unit fraction, and compute such
quotients. For example, create a story context for 4  (1=5), and use a visual fraction
model to show the quotient. Use the relationship between multiplication and division to
explain that 4  (1=5) = 20 because 20  (1=5) = 4.
c. Solve real world problems involving division of unit fractions by non-zero whole numbers and division of whole numbers by unit fractions, e.g., by using visual fraction models and equations to represent the problem. For example, how much chocolate will each person get if 3 people share 1=2 lb of chocolate equally? How many 1=3-cup servings are in 2 cups of raisins?

##### Understand ratio concepts and use ratio reasoning to solve problems.

1. Understand the concept of a ratio and use ratio language to describe a ratio rela-
tionship between two quantities. For example, \The ratio of wings to beaks in the bird
house at the zoo was 2 : 1, because for every 2 wings there was 1 beak. \For every vote
2. Understand the concept of a unit rate a=b associated with a ratio a : b with b 6= 0,
and use rate language in the context of a ratio relationship. For example, \This recipe
has a ratio of 3 cups of
our to 4 cups of sugar, so there is 3=4 cup of
our for each cup
of sugar. \We paid \$75 for 15 hamburgers, which is a rate of \$5 per hamburger.”11
3. Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by
reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams,
or equations.
b. Solve unit rate problems including those involving unit pricing and constant
speed. For example, if it took 7 hours to mow 4 lawns, then at that rate, how many lawns
could be mowed in 35 hours? At what rate were lawns being mowed?
c. Find a percent of a quantity as a rate per 100 (e.g., 30% of a quantity means
30/100 times the quantity); solve problems involving nding the whole, given a part and
the percent.

##### Apply and extend previous understandings of multiplication and division to divide fractions by fractions.

11Expectations for unit rates in this grade are limited to non-complex fractions.
1. Interpret and compute quotients of fractions, and solve word problems involving
division of fractions by fractions, e.g., by using visual fraction models and equations to
represent the problem. For example, create a story context for (2=3)  (3=4) and use
a visual fraction model to show the quotient; use the relationship between multiplica-
tion and division to explain that (2=3)  (3=4) = 8=9 because 3=4 of 8=9 is 2=3. (In
general, (a=b)  (c=d) = ad=bc:) How much chocolate will each person get if 3 people
share 1=2 lb of chocolate equally? How many 3=4-cup servings are in 2=3 of a cup of
yogurt? How wide is a rectangular strip of land with length 3=4 mi and area 1=2 square mi?
3. Fluently add, subtract, multiply, and divide multi-digit decimals using the standard
algorithm for each operation.