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Example Questions
例子问题# 1:How To Solve For A Variable As Part Of A Fraction
Findx.
None
Cross multiply:
Example Question #2 :How To Solve For A Variable As Part Of A Fraction
The numerator of a fraction is the sum of 4 and 5 times the denominator. If you divide the fraction by 2, the numerator is 3 times the denominator. Find the simplified version of the fraction.
Let numerator = N and denominator = D.
According to the first statement,
N = (D x 5) + 4.
According to the second statement, N / 2 = 3 * D.
Let's multiply the second equation by –2 and add itthe first equation:
–N = –6D
+[N = (D x 5) + 4]
=
–6D + (D x 5) + 4 = 0
–1D + 4 = 0
D = 4
Thus, N = 24.
Therefore, N/D = 24/4 = 6.
例子问题# 1:How To Solve For A Variable As Part Of A Fraction
我f, what is the value of?
Start by cross multiplying to get the equation
.
Then simplify by subtractingfrom each side to get the solution,
.
例子问题# 1:How To Solve For A Variable As Part Of A Fraction
我f, then what isequal to?
We start by solving for x inby multiplying 4 and 15, which gives us.
Then substituting 60 for x in,
gives us
which equals 0.
Example Question #3 :How To Solve For A Variable As Part Of A Fraction
我f, and, what is the value of?
Start by cross multiplying which gives us.
Simplify by dividing both sides bywhich gives us.
我solateby dividing both sides byand then addingto both sides, which gives us.
例子问题# 1:How To Solve For A Variable As Part Of A Fraction
我f, andwhat is the value of?
Start by cross multiplying which gives us
.
Divide both sides by 12 and simplify which gives us.
Since, we only take the positive square root as the solution,.
例子问题# 1:How To Solve For A Variable As Part Of A Fraction
我f, then what is the value of?
3/38
none of these
9/114
7/12
38/3
38/3
cross multiply:
(6)(19) = 9x
114=9x
x = 38/3