In the expression above, a, b, and c are different numbers and each is

Question

(a/b)/c

In the expression above, a, b, and c are different numbers and each is one of the numbers 3, 4, or 7. What is the least possible value of the expression?
(A) 21/4
(B) 3/28
(C) 4/21
(D) 7/12
(E) 3/7

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sashiim20 · Answer

A is improper fraction hence it is bigger than all other options.
Check all other options.
B) 3/28 = 0.107
C) 4/21 = 0.190
D) 7/12 = 0.583
E) 3/7 = 0.428

Least possible value of (a/b)/c is  \frac{3}{28}  = 0.107. Answer B...

generis · Answer

(a/b)/c = a/(bc) .

The fraction with the least value will have the smallest possible numerator and the largest possible denominator - i.e., the fewest parts of many.

The two larger values, 4 and 7 multiplied, make the largest denominator. Choice (B), 3/28 is the smallest.

The only close answer is 4/21. Lots of ways to check that it isn't the smaller value; one is that 4/21 is close to 1/5 and 3/28 is close to 1/9.

Answer (B)

BrentGMATPrepNow · Answer

(a/b)/c = (a/b)/(c/1)
= (a/b)(1/c)
= a/(bc)

So, we want to minimize the value of a/(bc)
To do so, we must MINIMIZE the numerator (a) and MAXIMIZE the denominator (bc)
So, let a = 3, and let b = 4 and c = 7

So, (a/b)/c = a/(bc) = 3/(4 x 7)
= 3/28

Answer: B

RELATED VIDEO
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JeffTargetTestPrep · Answer

We can simplify the given expression:
 
(a/b)/c = a/(bc)
 
To make a fraction’s value as small as possible, we need to make the numerator as small as possible and the denominator as large as possible.
 
Thus, we can let a = 3, b = 4, and c = 7, and we have:
 
3/28
 
Answer: B

danlew · Answer

Working from answer choices.
A = 21/4. Not possible as the numerator can only be 3, 4 or 7.

B=3/28. Possible, if a=3, and either b is 4 and c is 7 or vice versa.

Question asks for least possible value. All other choices are bigger than 3/28, so B

ksrivatsa · Answer

a/b/c, Just substitute the given values in the following fraction.
3/4/7
i.e, 3/4/7/1, which is nothing but,
3/4 * 1/7= 3/28

ydmuley · Answer

(a/b)/c a, b and c can be any of these three different numbers. - 3, 4 & 7. We have to find the least possible value of the equation. So, we must increase the denominator - means we will take bigger numbers to the denominator and smaller ones to numerator. after simplying above quation we get \frac{a}{bc} a - minimum value = 3 , b and c can take remaining values = 4 * 7 (or vice a versa) = 28 We get \frac{3}{28} Hence, Answer is B 1 Kudos if you like :-D

Pritishd · Answer

Maximize the denominator in order to get the least value of the fraction. Hence, choose the largest of the three numbers i.e. 7 as the value of the overall denominator (c), and next largest value as the value of b.

(3/4)/7 = 3/28 (Option B)

(3/4)/7 = 3/28 (Option B)

bumpbot · Answer

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