Before you can add or subtract fractions with different denominators.you first have to find common denominators. subtract the numerators and reduce fraction.
Adding fractions make sure numbers are same add the numerators and put it over the denominator,simplify the fraction if needed
Let's convert this fraction to an equal fraction which holds a denominator of 100, since it is a power of 10.
Since the denominator can be multiplied by 5 to achieve 100, we can multiply the entire fraction by 5 to create an equivalent fraction that has a denominator of 100:
17/20 = (17*5)/(20*5) = 85/100
To obtain a decimal from this fraction, take the numerator and move its decimal one place to the left for every 0 in the denominator. Since our denominator has two zeros, we will need to move the decimal place on the 85 two places to the left.
This gives us an answer of .85, which can also be expressed as 0.85.
Answer:
21
Step-by-step explanation:
cross multiply
42 x 24 = 48x
1008 = 48x
x = 21
One month = 5000
Number of months before the spark plugs need to change :
15000 ÷ 5000 = 3
The sparks can last 3 months before it needs to be changed.
Number of times it need to change in a year = 12 ÷ 3 = 4
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Answer : It needs to be change 4 times a year.
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