First, it takes one minute to fry two eggs at the same time. Take out an fried egg, flip an fried egg and put in a new egg, which takes one minute; At this time, fry an egg, then turn over the fried eggs in the pot, put in the fried eggs taken out for the first time, and then fry the remaining two fried eggs in one minute.

Extended data:

Common similar problems

Spiders have eight legs, dragonflies have six legs and two pairs of wings, and cicadas have six legs and 1 pairs of wings. These three kinds of bugs are *** 18, with 1 18 legs and 20 pairs of wings. How many bugs are there in each species?

Solution: Because both dragonflies and cicadas have six legs, they can be divided into "eight legs" and "six legs" according to the number of legs. You can calculate eight legs by formula.

Number of spiders = (118-6×18) ÷ (8-6)

=5 (only).

So we know that hexapod *** 18-5= 13 (only).

In other words, there are 13 dragonflies and cicadas, and they have 20 pairs of wings. Use the formula again.

Cicada number = (13× 2-20) ÷ (2-1) = 6 (only).

So the number of dragonflies is 13-6=7 (only).

There are five spiders, seven dragonflies and six cicadas.

2. In a math exam, 52 people in the class took part in five questions, and * * * got it right 18 1 question. It is known that everyone answered at least 1 question correctly, 7 people answered 1 question correctly, 6 people answered all 5 questions correctly, and the same number of people answered 2 and 3 questions correctly, so the number of people who answered 4 questions correctly.

Solution: There are 52-7-6=39 people with 2, 3 and 4 questions.

They got it right:181-1× 7-5× 6 =144 (Dao).

Because there are as many people who answered question 2 as question 3, we can regard them as those who answered question 2.5 ((2+3)÷2=2.5).

Number of rabbit feet =4, number of chicken feet =2.5,

Total number of feet = 144, total number of heads =39.

There are four problems: (144-2.5× 39) ÷ (4-2.5) = 31(person).

A: 365,438+0 people answered four questions correctly.

Baidu Encyclopedia-Chicken and Rabbit in the Same Cage (Olympiad)