2.( 1 1 1×66- 185×8)÷37= 158.

(37×3×66-37×5×8)÷37= 158

4. If an integer with all digits of 1 is divisible by 333333, then the number of 1 in this integer is at least _ _ _ _.

6. Original price of a toothpaste per box 15 yuan. In order to promote sales and reduce the price, the sales volume has tripled and the income has increased by three-fifths, so the price of a box of toothpaste has been reduced by _ _ _ _ _ _.

7. Use each of the nine numbers 1, 2, 3, 4, 5, 6, 7, 8 and 9 once to form a three-digit number divisible by 9. The sum of these three numbers is required to be as large as possible. So, this sum is _ _ _ _.

954+873+62 1=2448

8.4 1 digit 55…5 □99…9 (including 20 of 5 and 9) can be divisible by 7, so the number in the middle square is -5—

9. Three children, A, B and C, go to buy ice cream. If they buy three ice creams with the money brought by A, the difference is 0.63 yuan; If you buy three ice creams with the money brought by B, it is still worse than 0.8 yuan; If you buy three ice creams with the money brought by three people, it will be 0.27 yuan more; It is known that C brings 0.4 1 yuan, so it costs _ _ 0.43 _ _ yuan to buy an ice cream.

Second, answer questions:

1. The express train and the local train are in opposite directions. The length of the express train is 280 meters and the length of the local train is 385 meters. It takes 1 1 sec to take the express train and watch the slow train pass. How many seconds does it take to sit on the local train and see the express pass by?

1 1×280÷385=8 (seconds)

2. A pile of apples in two plots 1, two apples in three plots, three apples in four plots, four apples in five plots, four apples in five plots and five apples in six plots. How many apples are there in this pile?

1 is less than the least common multiple of 2, 3, 4, 5 and 6.

60- 1=59 (piece)

4. There were 420 bricks, so several students could carry them, and how many bricks each student could carry. Later, a student was added, so each student moved two bricks less than originally planned. How many students are there? 14 people

420=2×2×3×5×7=30× 14=28× 15

There are x natives, and no one touches y bricks in each plan.

xy=420

(x+ 1)(y-2)=420

x= 14

y=30

Wish you success!