Sam rode his bike 2/5 of a mile and walked another 3/4 of a mile. How far did he travel?
The correct answer and explanation is :
To find out how far Sam traveled in total, we need to add the distance he rode on his bike and the distance he walked. The two distances are expressed as fractions: ( \frac{2}{5} ) of a mile and ( \frac{3}{4} ) of a mile.
Step 1: Find a common denominator
Before adding the two fractions, we need to find a common denominator. The denominators of the fractions are 5 and 4. The least common denominator (LCD) of 5 and 4 is 20 because 20 is the smallest number that both 5 and 4 divide evenly into.
Step 2: Rewrite the fractions with the common denominator
Now that we know the LCD is 20, we can rewrite each fraction with a denominator of 20:
- ( \frac{2}{5} ) becomes ( \frac{2 \times 4}{5 \times 4} = \frac{8}{20} )
- ( \frac{3}{4} ) becomes ( \frac{3 \times 5}{4 \times 5} = \frac{15}{20} )
Step 3: Add the fractions
Now that both fractions have the same denominator, we can add them together:
[
\frac{8}{20} + \frac{15}{20} = \frac{8 + 15}{20} = \frac{23}{20}
]
Step 4: Convert the improper fraction to a mixed number
The result ( \frac{23}{20} ) is an improper fraction, meaning the numerator (23) is larger than the denominator (20). To convert this to a mixed number, divide 23 by 20:
[
23 \div 20 = 1 \text{ with a remainder of } 3
]
So, ( \frac{23}{20} ) is equal to ( 1 \frac{3}{20} ) miles.
Final Answer:
Sam traveled a total of ( 1 \frac{3}{20} ) miles.
Explanation:
By adding the two fractions after finding a common denominator, we calculated that Sam’s total travel distance was more than 1 mile, but less than 2 miles. The mixed number ( 1 \frac{3}{20} ) miles represents the total distance Sam traveled, combining both his biking and walking activities.