Read the following and answer the questions that follow
XYZ organization got into the business of delivering groceries to home at the beginning of the last month. They have a two-day delivery promise. However, their deliveries are unreliable. An order booked on a particular day may be delivered the next day or the day after. If the order is not delivered at the end of two days, then the order is declared as lost at the end of the second day. XYZ then does not deliver the order, but informs the customer, marks the order as lost, returns the payment and pays a penalty for non-delivery.
The following table provides details about the operations of XYZ for a week of the last month. The first column gives the date, the second gives the cumulative number of orders that were booked up to and including that day. The third column represents the number of orders delivered on that day. The last column gives the cumulative number of orders that were lost up to and including that day.
It is known that the numbers of orders that were booked on the 11th, 12th, and 13th of the last month that took two days to deliver were 4, 6, and 8 respectively.
[CAT 2020 S3]
34) Among the following days, the largest fraction of orders booked on which day was lost?
(1) 13th
(2) 14th
(3) 16th
(4) 15th
35) On which of the following days was the number of orders booked the highest?
(1) 14th
(2) 13th
(3) 12th
(4) 15th
36) The delivery ratio for a given day is defined as the ratio of the number of orders booked on that day which are delivered on the next day to the number of orders booked on that day which are delivered on the second day after booking. On which of the following days, was the delivery ratio the highest?
(1) 15th
(2) 13th
(3) 16th
(4) 14th
37) The average time taken to deliver orders booked on a particular day is computed as follows. Let the number of orders delivered the next day be x and the number of orders delivered the day after be y. Then the average time to deliver order is (x+2y)/(x+y). On which of the following days was the average time taken to deliver orders booked the least?
(1) 16th
(2) 14th
(3) 13th
(4) 15th
Solution
34

From the table, The cumulative orders booked and the cumulative orders lost can be calculated for each day but orders delivered by that day has two elements in it. It comprises of orders booked from previous day and the day before.. Thus the table can be re-written as follows,

As said, The orders delivered has two elements in it. Let
Orders booked from previous day = T1
Orders booked from Two days early = T2
It is known that the numbers of orders that were booked on the 11th, 12th, and 13th of the last month that took two days to deliver were 4, 6, and 8 respectively.

From the above table,
Total orders booked on 13th = T1(14
th) + T2(15
th) + Orders lost on 15
th orders booked on 13th = 21 + 8 + 2 = 31
Total orders booked on 14
th = T1(15
th) + T2(16
th) + Orders lost on 16
th
30 = 15 + 3 + 12
Follow the same set of steps to fill the rest.
Total orders booked on 15
th = T1(16
th) + T2(17
th) + Orders lost on 17
th
28 = 8 + 8 +12
Total orders booked on 16th = T1(17
th) + T2(18
th) + Orders lost on 18
th
25 = 13 + 10 + 2
Total orders booked on 17
th = T1(18
th) + T2(19
th) + Orders lost on 19
th
25 = 3 + 13 + 9
Total orders booked on 13
th = T1(14
th) + T2(15
th) + Orders lost on 15
th
31 = 21 + 8 + 2
Total orders booked on 12
th = T1(13
th) + T2(14
th) + Orders lost on 14
th
14 = 7 + 6 + 1

Considering options,

On comparing the fractions,
2812is the largest.
Hence, Day 15th has the largest fraction of orders booked on which day was lost.
Answer: (4) 15th
35

On considering options,
Day 13th has the largest number of orders booked.
Answer: (2) 13th
36)

Delivery ratio = Orders delivered on two days afterOrders delivered on the next day
Find delivery ratios for the given options.
13th = 21/8
14th = 15/3
15th = 8/8
16th = 13/10
Day 14th has the highest delivery ratio.
Answer: (4) 14th
37)
Average time taken = x+yx+2y
= x+yx+y+x+yy
= 1+x+yy

The lowest average time taken to deliver the orders is on the day 14th
Answer: (2) 14th
Answer:
34) (4) 15th
35) (2) 13th
36) (4) 14th
37) (2) 14th