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How do you solve #5/f=35/21#?

Answer 1

Eva Abramson

#f=3#

Cross multiply:

#5*21=35*f#

#35f=105#

#f=3#

These two are equivalent fractions. The second fraction can be derived from the first one. In order for them to be equivalent, the numerator and denominator both have to be multiplied/divided by the same number.

5 is multiplied by 7 to get 35, so f must also be multiplied by 7 to get 21.

#7*f=21#

#f=3#

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Answer 2

Hazel Anglin

#f=3#

#5/f=35/21# (First, multiply both sides by f)

#5=35/21 f# (Multiply both sides of the reciprocal of #35/21# which is #21/35#)

#5(21/35)=f# (Distribute 5 to the numbers in bracket)

#21/7 = f# (Simplify the left side)

#3=f#

Check the answer by plugging it into the original equation:

#5/3=35/21# (7 if a factor for the right side to simplify it)

#5/3=5/3#

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Answer 3

Eli Assouline

To solve the equation 5/f = 35/21, you can cross-multiply. Multiply 5 by 21 and set it equal to f multiplied by 35. Simplify the equation and solve for f.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.