□×△×□△=△△△
3×7×37=777
Then□ = (3), △ = (7)
Analysis: After dividing the two sides by △, it becomes □×□△ =11.
Only 3× 37 =11,so □ = 3 ,□△ = 37.
Question 2: Xiao Ning took one of the factors 2 1 as 12 when doing multiplication, and the product obtained was 207 less than the correct product. What is the right product?
Solution: The product is 9 times smaller than another factor, so another factor = 207/(2 1- 12) = 23.
23×2 1=483
The third question A caught up with B 40 meters ahead. The speed of B is 60 meters per minute, and the speed of A is 65 meters per minute. How many minutes after A leaves, can you catch up with B?
Solution: Catch-up time = distance difference/speed difference = 40/(65-60) = 8 minutes.
Xiaohua walks 45 meters per minute in the fourth lane, and Xiaohong walks 50 meters per minute. Three minutes later, Xiaohong turned to chase Xiaohua. How many minutes can Xiaohong catch up with Xiaohua?
Solution: distance difference = 3× (45+50) = 285 m.
Catch-up time = 285/(50-45) = 57 minutes.
Question 5: There are 900 peach and pear trees in the orchard. The number of peach trees is more than four times that of pears. 10. How many trees are there in the orchard?
Solution: After subtracting 10 trees from peach trees, it is 4 times that of pear trees, and the total number is 5 times that of pear trees.
Pear tree: (900- 10)/5 = 178
Peach tree: 900- 178 = 722