Logical thinking interview questions-java backend interview

Question 1

4 2 12 28 80 Write the following number

A.124 B.96 C.216 D.348

Correct solution C

28=(12+2)*2

80=( 12+28)*2

216=(80+28)*2

The second question

A, B, C, D and E play chess together. Every two games, count the number of games. Know: Match A has 4 sets, Match B has 3 sets, Match C has 2 sets, Match D has 1 set. What is the number of sets in Match E?

Use A-B to represent the match between A and B

__Black Pig's answer Baidu homework Help

A match 4 sets A-B, A-C, A-D, A-E

D match 1 set and already face A-D and then play with D

Look at B match 3 sets apart from A and D, all B-C, B-E

C It has been determined that there will be another 2 sets of games

Known: E will compete with A and B for a total of 2 sets

pmltt129’s answer Baidu knows

The third question

At a certain time, the clock hand is between 10 o’clock and 11 o’clock. At this time, again After 6 minutes, the minute hand and the hour hand 3 minutes before this moment are in the opposite direction and in a straight line. What time is it at this moment?

The hour hand moves 30 degrees per hour and 0.5 degrees per minute

The minute hand moves per minute Go 6 degrees

Now, assuming that 12 o'clock is 0 degrees

Assume that the current time is 10 o'clock X minutes

Then the current hour hand position is: 10 * 30 + X * 0.5 = 300 + The current minute hand position is: + (X - 3) * 0.5 = 298.5 + So there is:

298.5 +

A person worked for 24 consecutive days and earned 190 yuan (a daily wage of 10 yuan, half-day work on Saturday, half-day salary; Sunday off, no salary). It is known that he started working on a certain day in late January, and the 1st of this month happened to be a Sunday. Question: When is the day in February when this person’s part-time job ends? ( )

A 16

B 17

C 18

D 19

Answer C

work week is 55 yuan, total Earn 190, 55*3+25=190, 25 is two working days plus one Saturday. If the 25 is earned in February, the remaining days cannot make up three full weeks (Thursday must be preceded by Monday) , Tuesday..), so this person starts working on Thursday in late January.

January 1st is Sunday, then the 5th, 12th, 19th, and 26th are Thursdays. If it is on the 19th, January has 31-19+1=13 days, and February has 11 days. Obviously there is no answer, so this person started working on January 26, 31-26+1=6, and worked 24-6=18 in February.

Question 5

It takes 4 minutes to saw a steel pipe into two sections. How many minutes does it take to saw into 8 sections?

It takes one sawing to cut into two sections, two sawings to cut into three sections, and the same is true for sawing into 8 sections. End 8 needs to be sawed 7 times

4*7=28

Question 6

There is a pasture where 27 cows are known to eat all the grass in 6 days. Raising 23 cows, they eat all the grass in 9 days. If we raise 21 cows, how many days will it take to eat all the grass on the pasture? And the grass in the pasture is constantly growing. ”

Suppose one head eats one grass a day

27*6=162 The original grassland plus 6 days long

23*9=207 The original grassland plus 9 days long

Suppose the original grassland has x, grow y every day

y+6x=162

y+9x=207

y=72 12.

Escape **Tornado**

Question 7

Each aircraft has only one fuel tank, and the aircraft can refuel each other (note that it is each other, there is no tanker). One tank of fuel is enough for one aircraft to orbit the earth. Flying half a circle, question: In order for at least one plane to circle the earth and return to the airport where it took off, how many planes must be dispatched? (All planes take off from the same airport and must return to the airport safely, no hits are allowed

ABC 3 planes take off at the same time, at the 1/8th point, C fills up the fuel for AB, C returns, at the 1/4th point, B fills up the fuel for A, B returns, A reaches the 1/2 point, C heads in the other direction from the airport After taking off, at 3/4, C shares the remaining fuel with A, who has an empty tank. At the same time, B takes off from the airport. AC arrives at 7/8 and shares the remaining fuel with B. It happens that 3 planes return at the same time, so there are 3 planes. 5 sorties

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