2/5×(-3/7)-1/6+1/14×2/5 chapter rational number. using Appropriate pro...
2/5 x (-3/7) - 1/6 x 3/2 + 1/14 x 2/5
= 2/5 x (-3/7) + 1/14 x 2/5 - (1/6 x 3/2) (by commutativity)
= 2/5(-3/7 + 1/14) - 1/4
= 2/5{(-6 + 1)/14} - 1/4 (by distributivity)
= 2/5(-5/14) - 1/4
= -1/7 - 1/4
= (-4-7)/28
= -11/28
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2/5×(-3/7)-1/6+1/14×2/5 chapter rational number. using Appropriate pro...
Simplifying the given expression: 2/5 × (-3/7) - 1/6 1/14 × 2/5
First, let's simplify each multiplication separately:
1. 2/5 × (-3/7):
To multiply fractions, we multiply the numerators together and the denominators together. So, 2/5 × (-3/7) = (2 × -3) / (5 × 7) = -6/35.
2. 1/6 1/14 × 2/5:
To multiply mixed numbers, we convert them to improper fractions. 1/6 1/14 can be written as (6/6 + 1/6) × (14/14 + 1/14) = 7/6 × 15/14 = (7 × 15) / (6 × 14) = 105/84.
Now, let's substitute these values back into the original expression:
-6/35 - 105/84.
Next, we need to find a common denominator to combine these fractions.
Finding a common denominator:
The least common multiple (LCM) of 35 and 84 is 420. Therefore, we need to convert both fractions to have a denominator of 420.
Multiplying the first fraction by (12/12) and the second fraction by (5/5), we get:
(-6/35) × (12/12) = -72/420
(105/84) × (5/5) = 525/420
Now, we can combine the fractions:
-72/420 - 525/420.
Subtracting the fractions:
To subtract fractions with the same denominator, we subtract the numerators and keep the common denominator.
(-72/420) - (525/420) = (-72 - 525)/420 = -597/420.
Simplifying the fraction:
To simplify the fraction, we divide both the numerator and denominator by their greatest common divisor (GCD), which is 3.
(-597/3)/(420/3) = -199/140.
Therefore, the simplified expression is -199/140.
In conclusion, the value of the expression 2/5 × (-3/7) - 1/6 1/14 × 2/5 is -199/140.
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