In a certain flight 3/4 of its seats were booked including 2/3 of its

Let total seats = 100

Business class seats \(= \frac{3}{5} * 100 = 60\)

Number of booked business class seats \(= \frac{2}{3} * 60 = 40\)

So, Number of non - booked business class seats = 60 – 40 = 20

Total booked seats \(= \frac{3}{4} * 100 = 75\)

Total number of non - booked seats = 100 – 75 = 25.

Percentage o non - business class seats = \(\frac{(Number of non - booked business class seats)}{(Total number of non - booked seats)} * 100\)
 \(= \frac{20}{25} * 100\)
 = 80%

Answer (D).

solve using 2x2 matrix
---B--------NB----total
BC--2*x/3-- 12 ------x
NBC-- ------ 60-x
Total -- 45 --- 15-- 60
let total seats ; 60
Booked ; 60*3/4 ; 45 and Not booked ; 15
Business class booked 3/5*60 ; 36=x so BC booked ; 2*36/3 = 24 and Not booked BC ; 12
so not booked Business class seats ; 12/15 ; 80 %
IMO D

In a certain flight 3/4 of its seats were booked including 2/3 of its business class seats. If 3/5 of its seats were business class, then what percent of the seats that were not booked were business class?

(A) 20%
(B) 35%
(C) 40%
(D) 80%
(E) 90%

assume that total seats is 60

2/5 seats of 60 is business, so total business =36
2/3 of the 36 business seats were booked = 24
therefore 36-24=12 business seats were unbooked
the question ask what percent of the seats that were not booked were business class
\(\frac{12}{60(1/4)}\)= 80%

D

Edited:
IMO it's D.
Let the total number be 60.
Then we can have a table :
| B | Not B |
BC | 24 | 12 | =36
NBC | 21 | 3 | =24
Sum |45 | 15 | =60

We are asked 12 out of 15 which is 80%. (Sorry, the table is pretty ugly )

In a certain flight 3/4 of its seats were booked including 2/3 of its business class seats. If 3/5 of its seats were business class, then what percent of the seats that were not booked were business class?

(A) 20%
(B) 35%
(C) 40%
(D) 80%
(E) 90%

Let us consider 100 Seats, since this is a % question and there is no Fraction in the options.
Given 1 : 3/4 Total Seats filled = 75% = 75 seats. Total Seats Vacant = (100-75) = 25
Given 2 : 3/5 of Total Seats is Business Class = 60 out of 100 Seats and 2/3 of 60 is filled up = 40 seats of Business call filled up
Therefore vacant Business class seats = 20
Question is : What is the % of vacant Business class seats out of the total Vacant seats
Ans = Vacant Business class seats / Total Vacant Seats = 20/25 = 80% . Answer - D

Regards KDgupta

Let us consider 100 Seats, since this is a % question and there is no decimal percentages in the options.
Given 1 : 3/4 Total Seats filled = 75% = 75 seats. Total Seats Vacant = (100-75) = 25
Given 2 : 3/5 of Total Seats is Business Class = 60 out of 100 Seats and 2/3 of 60 is filled up = 40 seats of Business call filled up
Therefore vacant Business class seats = 20
Question is : What is the % of vacant Business class seats out of the total Vacant seats
Ans = Vacant Business class seats / Total Vacant Seats = 20/25 = 80% . Answer - D

Regards KDgupta

In a certain flight 3/4 of its seats were booked including 2/3 of its business class seats. If 3/5 of its seats were business class, then what percent of the seats that were not booked were business class?

Lets say total seats including economy and business class seats are 60
3/5 of its seats are business = \(\frac{3}{5}\) * 60 = 36
3/4 of total seats were booked, that is \(\frac{3}{4}\)*60 = 45
this 45 includes 2/3 of business class = \(\frac{2}{3}\) * 36 = 24
total economy seats = 60 - 36 = 24
so this 45 must include economy booked seats as = 45 - 24 = 21
Not booked business are 36-24 = 12
Total % not booked business class were = \(\frac{12}{60}\) = \(\frac{1}{5}\) = 20%

A is the answer!

i thought to take the number of not booked bsusiness class seats to a total number of seats [(X/5 )/ X)] * 100 %, getting 20 % trap answer.

but from the question stem, i cannot infer to take [(X/5 )/X/4)] * 100 %. Can some one please explain, how do we understand weather it is to take [(X/5 )/ X)] or [(X/5 )/X/4)].

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