# You try it example 11 1 18 simplify 5 24 11 36

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Answer:25/72You Try It!EXAMPLE 11.Simplify:-1124-118.Simplify:-524-1136Solution.Prime factor the denominators in compact form using exponents.24 = 2·2·2·3 = 23·3118 = 2·3·3 = 21·32To find the LCD, write down each factor that appears to the highest power ofthat factor that appears. The factors that appear are 2 and 3.The highestpower of 2 that appears is 23. The highest power of 3 that appears is 32.LCM = 23·32Keep highest power of each factor.= 8·9Expand: 23= 8 and 32= 9.= 72.Multiply.
284CHAPTER 4.FRACTIONSCreate equivalent fractions with the new LCD, then subtract.-1124-118=-11·324·3-1·418·4Equivalent fractions with LCD=72.=-3372-472Simplify numerators and denominators.=-33-472Keep LCD; subtract numerators.=-3772Simplify numerator.Of course, negative divided by positive yields a negative answer, so we can alsowrite our answer in the form-1124-118=-3772.Answer:-37/72Comparing FractionsThe simplest way to compare fractions is to create equivalent fractions.You Try It!EXAMPLE 12.Arrange the fractions-1/2 and-4/5 on a number line, thenCompare-3/8 and-1/2.compare them by using the appropriate inequality symbol.Solution.The least common denominator for 2 and 5 is the number 10. First,make equivalent fractions with a LCD equal to 10.-12=-1·52·5=-510-45=-4·25·2=-810To plot tenths, subdivide the interval between-1 and 0 into ten equal incre-ments.0-11245510810Because-4/5 lies to the left of-1/2, we have that-4/5 isless than-1/2, sowe write-45<-12.Answer:-12<-38
4.4.ADDING AND SUBTRACTING FRACTIONS285ExercisesIn Exercises1-10, list the multiples the given numbers, then list the common multiples.Select theLCM from the list of common multiples.1. 9 and 152. 15 and 203. 20 and 84. 15 and 65. 16 and 206. 6 and 107. 20 and 128. 12 and 89. 10 and 610. 10 and 12In Exercises11-20, for the given numbers, calculate the LCM using prime factorization.11. 54 and 1212. 108 and 2413. 18 and 2414. 36 and 5415. 72 and 10816. 108 and 7217. 36 and 2418. 18 and 1219. 12 and 1820. 12 and 54In Exercises21-32, add or subtract the fractions, as indicated, and simplify your result.21.712-11222.37-5723.19+1924.17+3725.15-4526.35-2527.37-4728.67-2729.411+91130.1011+41131.311+41132.37+27
286CHAPTER 4.FRACTIONSIn Exercises33-56, add or subtract the fractions, as indicated, and simplify your result.33.16-1834.79-2335.15+2336.79+2337.23+5838.37+5939.47-5940.35-7841.23-3842.25-1843.67-1644.12-1445.16+2346.49+7847.79+1848.16+1749.13+1750.56+1451.12-2752.13-1853.56-4554.12-1955.13+1856.16+79In Exercises57-68, add or subtract the fractions, as indicated, by first using prime factorization to findthe least common denominator.57.736+115458.754+72459.718-51260.554-71261.736+75462.572+510863.724-53664.1154+77265.1112+51866.1124+1110867.1154-52468.754-524