1. Example-1
1. Simplify `1/2+3/4-7/6`
Solution: `1/2+3/4-7/6`
`=(1)/(2) + (3)/(4) - (7)/(6)`
LCM of `2,4,6` is `12`Step-1: Prime factorization of `2,4,6` using factor by division method Step-2: Write each number as a product of primes, matching primes vertically when possible Step-3: Bring down the primes in each column. The LCM is the product of these factors 2 | = | 2 | | | | 4 | = | 2 | × 2 | | | 6 | = | 2 | | × 3 | |
| LCM | = | 2 | × 2 | × 3 | = 12 |
`:.` LCM of `2,4,6` is `12` `=(1 xx 6)/(2 xx 6) + (3 xx 3)/(4 xx 3) - (7 xx 2)/(6 xx 2)` (Change into equivalent fractions with the LCD 12)
`=(6)/(12) + (9)/(12) - (14)/(12)` (Simplify the numerators and denominators)
`=(6 + 9 - 14)/(12)`
`=(1)/(12)`
2. Simplify `8/9*35/12-7/15`
Solution: `8/9*35/12-7/15`
`=(8)/(9) xx (35)/(12) - (7)/(15)`
`=(8xx35)/(9xx12) - (7)/(15)`
`=(2*2*2xx5*7)/(3*3xx2*2*3) - (7)/(15)` (Find factors)
`=(cancel{(2)}*cancel{(2)}*2xx5*7)/(3*3xxcancel{(2)}*cancel{(2)}*3) - (7)/(15)` (Remove common factors)
`=(70)/(27) - (7)/(15)`
LCM of `27,15` is `135`Step-1: Prime factorization of `27,15` using factor by division method Step-2: Write each number as a product of primes, matching primes vertically when possible Step-3: Bring down the primes in each column. The LCM is the product of these factors 27 | = | 3 | × 3 | × 3 | | | 15 | = | 3 | | | × 5 | |
| LCM | = | 3 | × 3 | × 3 | × 5 | = 135 |
`:.` LCM of `27,15` is `135` `=(70 xx 5)/(27 xx 5) - (7 xx 9)/(15 xx 9)` (Change into equivalent fractions with the LCD 135)
`=(350)/(135) - (63)/(135)` (Simplify the numerators and denominators)
`=(350 - 63)/(135)`
`=(287)/(135)`
3. Simplify `3 1/2+1 3/4-7/6`
Solution: `3 1/2+1 3/4-7/6`
`=3 (1)/(2) + 1 (3)/(4) - (7)/(6)`
Converting mixed number to improper fraction `=(3xx2+1)/(2) + (1xx4+3)/(4) - (7)/(6)`
`=(7)/(2) + (7)/(4) - (7)/(6)`
LCM of `2,4,6` is `12`Step-1: Prime factorization of `2,4,6` using factor by division method Step-2: Write each number as a product of primes, matching primes vertically when possible Step-3: Bring down the primes in each column. The LCM is the product of these factors 2 | = | 2 | | | | 4 | = | 2 | × 2 | | | 6 | = | 2 | | × 3 | |
| LCM | = | 2 | × 2 | × 3 | = 12 |
`:.` LCM of `2,4,6` is `12` `=(7 xx 6)/(2 xx 6) + (7 xx 3)/(4 xx 3) - (7 xx 2)/(6 xx 2)` (Change into equivalent fractions with the LCD 12)
`=(42)/(12) + (21)/(12) - (14)/(12)` (Simplify the numerators and denominators)
`=(42 + 21 - 14)/(12)`
`=(49)/(12)`
`=4 1/12` (Converting improper fraction to mixed number)
4. Simplify `2 3/4-1 5/7*1 3/4`
Solution: `2 3/4-1 5/7*1 3/4`
`=2 (3)/(4) - 1 (5)/(7) xx 1 (3)/(4)`
Converting mixed number to improper fraction `=(2xx4+3)/(4) - (1xx7+5)/(7) xx (1xx4+3)/(4)`
`=(11)/(4) - (12)/(7) xx (7)/(4)`
`=(11)/(4) - (12xx7)/(7xx4)`
`=(11)/(4) - (2*2*3xx7)/(7xx2*2)` (Find factors)
`=(11)/(4) - (cancel{(2)}*cancel{(2)}*3xxcancel{(7)})/(cancel{(7)}xxcancel{(2)}*cancel{(2)})` (Remove common factors)
`=(11)/(4) - 3`
LCM of `4,1` is `4`Step-1: Prime factorization of `4,1` using factor by division method Step-2: Write each number as a product of primes, matching primes vertically when possible Step-3: Bring down the primes in each column. The LCM is the product of these factors `:.` LCM of `4,1` is `4` `=(11)/(4) - (3 xx 4)/(1 xx 4)` (Change into equivalent fractions with the LCD 4)
`=(11)/(4) - (12)/(4)` (Simplify the numerators and denominators)
`=(11 - 12)/(4)`
`=(-1)/(4)`
This material is intended as a summary. Use your textbook for detail explanation. Any bug, improvement, feedback then
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