The unit price of milk in the shop is 2.6 yuan per box. The shop has a sales promotion on New Year's day. If you buy five boxes, you get one free. How much does it cost to buy 30 boxes of milk at least?

2.6 * (30 / 6 * 5) = 2.6 * 25 = 65 yuan

How much discount does the shop give one free for four

20% off. Suppose each piece is 2 yuan. Originally, it costs 10 yuan to buy 5 pieces. Now it costs 8 yuan to buy 4 pieces, and one free piece is equal to 5 pieces for 8 yuan

A store holds promotion activities. Scheme 1: sell the goods at 75% discount. Scheme 2: buy the goods at one time, 60 yuan for free if 200 yuan
1. Mr. Zhang bought 688 yuan goods and 768 yuan goods
Scheme 1: 688 and 768 are purchased according to scheme 1
Plan 2: 688 yuan will be purchased according to plan 1, and 768 yuan will be purchased according to plan 2
Plan 3: 688 plan 2 purchase, 768 yuan according to plan 1 purchase
Scheme 4: 688 and 768 are purchased according to scheme 2
Which plan is more reasonable for Mr. Zhang? And explain the reason
2. From the above calculation, what rules do you find when you buy between 600 and 800?

1. Square 1: saving (688 + 768) * 0.25 = 364 square 2: 688 * 0.25 + 768% 200 * 60 = 352 square 3: 688% 200 * 60 + 768 * 0.25 = 372 square 4: 768% 200 * 60 + 688% 200 * 60 = 360 teacher Zhang is more reasonable according to plan 3. Because the reverse money between 600-800 is 180180 / 0.25 = 720, so 720

There are 42 students in a class, and at least a few of them have their birthdays in the same month

4
In 12 months of a year, 42 divided by 12 equals 3 to 6, 3 + 1 = 4

There are 58 students in class 6 (1) of Yingbin primary school. Can two or more of them celebrate their birthdays in the same week?

Yes, there are 52 weeks in a year. If there is one birthday in a week, there are 52 people. There are 58 people in the class. On average, there must be two or more people who have birthdays in the same week

There are 44 students in class 6 (1) of Yingbin primary school. At least several of them have their birthdays in the same month

There are 12 months in a year, 44 / 12 = 3.8
At least
Eight of them had four birthdays and four had three

There are 65 bottles of three kinds of drinks at the party. On average, one bottle of a for every two people, one bottle of B for every three people and one bottle of C for every four people. How many people are there at the party

This problem is a common multiple problem. The minimum common multiple of 2.4.3 is 12. If it's 12 people, they will drink 13 bottles. Now it's 65 bottles. It's five times as many people, that's 60 people

There are 65 bottles of three kinds of drinks. Each person drinks one bottle of milk on average. Two people drink one bottle of coke. Four people drink one bottle of orange juice. How many people want to attend the party

Is it right? If it's right, it doesn't seem to work out, because the least common multiple of 1, 2, 4 is 4, but 65 is not a multiple of 4. If it's 63 bottles, there are x bottles of orange juice, 2x bottles of coke, 4x bottles of milk. X + 2x + 4x = 63 test: 36 + 36 △ 2 + 36 △ 4

The school will hold a parents' forum with 35 participants. If you prepare about 200 ml of drinks for each person, which shopping mall is the most cost-effective place to buy? The big bottle of 1200 ml is 10 yuan per bottle, and the small can of 200 ml is 2 yuan per bottle. A shopping mall will get one free for one big bottle, B shopping mall will get 10% discount, C shopping mall will get 30 yuan, 20% discount

35 people, 200 per person. Total 200 × 35 = 7000
1200+200=1400
7000÷1400=5
A: 10 × 5 = 50
B: 12 × 5 × 0.9 = 54 C: 12 × 5 × 0.8 = 48
So c-cost. This is about algorithm, the following is a detailed analysis

We should prepare enough food and drink for the party

I'll try, the translation is not good, hope to have a better answer
We shall prepare enough food and drinks for the party.

The unit price of milk in the shop is 2.6 yuan per box. The shop has a sales promotion on New Year's day. If you buy five boxes, you get one free. How much does it cost to buy 30 boxes of milk at least?