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Ch. R - Review of Basic Concepts
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063당신이 사용하는 게 아니라요?교과서 변경
1장, 문제 73

Add or subtract as indicated. Write answers in lowest terms as needed. 4341254\(\frac{3}{4}\) - 1\(\frac{2}{5}\)

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First, convert the mixed numbers to improper fractions. For 4(3/4), multiply the whole number 4 by the denominator 4 and add the numerator 3: \(4 \times 4 + 3 = 19\), so \(4(3/4) = \frac{19}{4}\). For 1(2/5), multiply 1 by 5 and add 2: \(1 \times 5 + 2 = 7\), so \(1(2/5) = \frac{7}{5}\).
Rewrite the expression using the improper fractions: \(\frac{19}{4} - \frac{7}{5}\).
Find the least common denominator (LCD) of the two fractions. The denominators are 4 and 5, so the LCD is the least common multiple of 4 and 5, which is 20.
Convert each fraction to an equivalent fraction with the denominator 20. For \(\frac{19}{4}\), multiply numerator and denominator by 5 to get \(\frac{95}{20}\). For \(\frac{7}{5}\), multiply numerator and denominator by 4 to get \(\frac{28}{20}\).
Subtract the numerators while keeping the denominator the same: \(\frac{95}{20} - \frac{28}{20} = \frac{95 - 28}{20} = \frac{67}{20}\). This is the result before simplifying. Check if the fraction can be simplified further.

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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Mixed Numbers and Improper Fractions

Mixed numbers combine a whole number and a fraction, such as 4(3/4). To perform arithmetic operations, it's often easier to convert mixed numbers into improper fractions, where the numerator is greater than the denominator, facilitating addition or subtraction.
추천 영상:
04:22
Dividing Complex Numbers

Fraction Subtraction

Subtracting fractions requires a common denominator. Once fractions share the same denominator, subtract the numerators while keeping the denominator constant. This process applies after converting mixed numbers to improper fractions.
추천 영상:
05:45
Radical Expressions with Fractions

Simplifying Fractions

After performing addition or subtraction, the resulting fraction should be simplified to its lowest terms by dividing numerator and denominator by their greatest common divisor (GCD). Simplification ensures the answer is expressed in the simplest form.
추천 영상:
05:45
Radical Expressions with Fractions