Mathematics
Grade 7
15 min
Compare fractions: word problems
Compare fractions: word problems
Tutorial Preview
1
Introduction & Learning Objectives
Learning Objectives
Identify fractions and quantities to be compared within word problems.
Determine appropriate strategies (common denominator, cross-multiplication, converting to decimals) to compare fractions.
Solve word problems involving the comparison of two or more fractions.
Interpret the results of fraction comparisons in the context of the word problem.
Justify fraction comparisons using mathematical reasoning.
Convert between mixed numbers and improper fractions when necessary for comparison.
Ever wonder who ate more pizza 🍕 or which recipe calls for less sugar? Comparing fractions helps us answer these everyday questions!
In this lesson, you'll learn how to tackle word problems that require comparing fractions. We'll explore different strategies to de...
2
Key Concepts & Vocabulary
TermDefinitionExample
FractionA number representing a part of a whole, expressed as a numerator over a denominator.In the fraction 3/4, 3 is the part and 4 is the whole.
NumeratorThe top number in a fraction, indicating how many parts of the whole are being considered.In 5/8, the numerator is 5.
DenominatorThe bottom number in a fraction, indicating the total number of equal parts the whole is divided into.In 5/8, the denominator is 8.
Equivalent FractionsFractions that represent the same value, even though they have different numerators and denominators.1/2, 2/4, and 3/6 are all equivalent fractions.
Common DenominatorA shared denominator for two or more fractions, which is necessary to add, subtract, or easily compare them.For 1/3 and 1/4, a common denominator is 12.
Least Common Multip...
3
Core Formulas
Comparing Fractions with a Common Denominator
If $\frac{a}{c}$ and $\frac{b}{c}$ are two fractions with the same positive denominator $c$, then $\frac{a}{c} > \frac{b}{c}$ if $a > b$, and $\frac{a}{c} < \frac{b}{c}$ if $a < b$.
To compare fractions, first find a common denominator. Once the denominators are the same, compare the numerators directly. The fraction with the larger numerator is the greater fraction.
Comparing Fractions using Cross-Multiplication
To compare $\frac{a}{b}$ and $\frac{c}{d}$, calculate the cross-products $a \times d$ and $b \times c$. If $a \times d > b \times c$, then $\frac{a}{b} > \frac{c}{d}$. If $a \times d < b \times c$, then $\frac{a}{b} < \frac{c}{d}$.
This method allows you to compare fractions without finding a comm...
5 more steps in this tutorial
Sign up free to access the complete tutorial with worked examples and practice.
Sign Up Free to ContinueSample Practice Questions
Challenging
Two identical water tanks are being filled. Tank A is 5/8 full. Tank B is 2/3 full. Which tank requires less water to be completely full?
A.Tank A
B.Both require the same amount.
C.The answer cannot be determined.
D.Tank B
Challenging
A bookstore has two shelves of the same length. The first shelf is 3/4 full of science books. The second shelf is 5/6 full of history books. If each science book has a width of 1/30 of the shelf length and each history book has a width of 1/36 of the shelf length, which shelf contains more books?
A.The first shelf (science books)
B.The second shelf (history books)
C.Both shelves contain the same number of books.
D.There is not enough information to decide.
Challenging
In a race, Runner A completed x/y of the distance and Runner B completed z/w of the distance. If you are given that the inequality x × w > y × z is true, what can you conclude about the distances they ran?
A.Runner A ran a greater fraction of the distance than Runner B.
B.Runner B ran a greater fraction of thedistance than Runner A.
C.They ran the same fraction of the distance.
D.No conclusion can be made without knowing the values of the variables.
Want to practice and check your answers?
Sign up to access all questions with instant feedback, explanations, and progress tracking.
Start Practicing Free