A maritime shipping company sends out at least 1 ship ship every day.

A maritime shipping company sends out at least 1 ship ship every day. For a certain seven days, is the total number of the ships departed more than 25?

(1) In one of the seven days, 20 ships departed.
(2) The numbers of ships departed are different each day.

Given: A maritime shipping company sends out at least 1 ship ship every day.
Asked: For a certain seven days, is the total number of the ships departed more than 25?

(1) In one of the seven days, 20 ships departed.
Since the maritime shipping company sends out at least 1 ship ship every day. In each of the other days, minimum ships departed=1
Total minimum number of ships departed in 7 days = 20+1+1+1+1+1+1 =26>25
SUFFICIENT

(2) The numbers of ships departed are different each day.
Since the maritime shipping company sends out at least 1 ship ship every day & The numbers of ships departed are different each day.
Minimum number of ships departed in 7 days = 1+2+3+4+5+6+7= 28>25
SUFFICIENT

IMO D

In my opinion, it helps to think of the solutions in terms of MINIMUM and MAXIMIUM.


A maritime shipping company sends out at least 1 ship ship every day. For a certain seven days, is the total number of the ships departed more than 25?

MINIMUM SHIPS DAILY = 1

(1) In one of the seven days, 20 ships departed.
Order of the days doesnt matter
Lets assume day 1 had 20 ships.
Remaining 6 days have MINIMUM 1 SHIP so total 6 ships

Total MINIMUM SHIPS for 7 days = 26

(1) IS SUFFICIENT


(2) The numbers of ships departed are different each day.
Lets see how many MINIMUM ships we can send if EACH DAY has MINIMUM 1 ship and EACH DAY has DIFFERENT NUMBER.

Day1 - 1
Day2 - 2
Day3 - 3
Day4 - 4
Day5 - 5
Day6 - 6
Day7 - 7

So MINIMUM 28 ships are departed...... (here 28 can be arrived by simple addition, but if the sequence was long we could use formula n(n+1)/2)

(2) IS SUFFICIENT


ANSWER: D - EACH IS SUFFICIENT

A maritime shipping company sends out at least 1 ship ship every day. For a certain seven days, is the total number of the ships departed more than 25?

(1) In one of the seven days, 20 ships departed.
(2) The numbers of ships departed are different each day.

Solution:
According to the first statement,lets assume the following ships being sent:
Day 1=1 ship
Day 2=1 ship
Day 3= 1 ship
Day 4=1 ship
Day 5=1 Ship
Day 6= 1 ship
Day 7 =20 ships

Total =Minimum 26 ships. Hence Sufficient.


According to second statement following can be the possibilities:

As per the information atleast 1 ship is sent out and according to second statement the number of ships which depart are different each day.Hence there can be follwing bare minimum possibilities:

Day 1=1 ship
Day 2=2 ships
Day 3= 3 ships
Day 4= 4 ships
Day 5= 5 ships
Day 6= 6 ships
Day 7= 7 ships
Hence total number of ship for 7 days =28 ships which is more than 25 ships.Hence sufficient.

Hence D IMO

A maritime shipping company sends out at least 1 ship ship every day. For a certain seven days, is the total number of the ships departed more than 25?

(1) In one of the seven days, 20 ships departed.
(2) The numbers of ships departed are different each day.

Question Stem Analysis:

We know from the question that there will be at least 1, i.e 1 or more than 1 ship will be sent everyday. we need find out the total number of ships departed in 7 days.

Statement One Alone:

In one of 7 days, 20 ships were sent, Therefore on the rest 6 days at least 1 ship per day will be sent, even if we assume the least number of ship, i.e 1, we get 20+1+1+1+1+1+1 =26 ships.
Hence statement one alone is sufficient to answer the question. Eliminate C & E

Statement two Alone:

The number of ships will be different, lets assume least number of ships starting from day 1, we get 1+2+3+4+5+6+7 = 28 ships for the 7 days.
Hence statement two alone is sufficient.

Answer is D

Statement 1
Number of ships departed on one of the seven days= 20
Minimum number of ships departed on rest of the six days= 1+1+1+1+1+1=6 {A maritime shipping company sends out at least 1 ship ship every day}

Hence minimum number of ship departed in seven days= 20+6=26>25

Sufficient

Statement 2
The numbers of ships departed are different each day.
Hence minimum number of ships departed in seven days= 1+2+3+4+5+6+7= 7*8/2=28>25

Sufficient

IMO D

shipping company sends out at least 1 ship ship every day = (given)

For a certain seven days, is the total number of the ships departed more than 25?


STATEMENT (1) In one of the seven days, 20 ships departed
suppose on 1st day = 20 ships departed
2nd day = 1 (given atleast 1 ship per day)
3rd day = 1
4th day = 1
5th day = 1
6th day = 1
7th day = 1

total minimum ships departed = 26 >25
hence we can give an answer yes
SUFFICIENT

STATEMENT (2) The numbers of ships departed are different each day
number of ships departed different each day and at least 1 ship every day
minimum number of ships departed in 7 days
suppose on 1st day =1 ship departed then
2nd day = 2
3rd day = 3
4th day = 4
5th day = 5
6th day = 6
7th day = 7
minimum number of ships departed in 7 days = 28>25
hence we can give an answer yes
SUFFICIENT

D is the answer

A maritime shipping company sends out at least 1 ship ship every day. For a certain seven days, is the total number of the ships departed more than 25?

(1) In one of the seven days, 20 ships departed.
From the given question we know that at least 1 ship departed in a week.
If one day out of seven was 20 ships, we assume that other six day there was at least 1 ship...
So we've got 20+6=26 ships departed.
26>25 - sufficient.


(2) The numbers of ships departed are different each day.
As departed ship numbers are different, and we have seven days, we can assume numbers:
1 day = 1 ship
2 day = 2 ships
3 day = 3 ships
4 day = 4 ships
5 day = 5 ships
6 day = 6 ships
7 day = 7 ships

So, 1+2+3+4+5+6+7=28
28>25 - sufficient.

D is the answer.

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