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Elementary school mathematics and multiplication problem reference
Elementary school mathematics and multiplication problem reference

Given the meaning of the sum of two numbers and how many times a large number is a decimal (or how many times a decimal is a large number), this kind of application problem is called the sum and multiple problem.

Sum of quantitative relations ÷ (multiple+1) = sum of smaller numbers-smaller. Number = higher number.

Smaller number × several times = larger number

Simple problem-solving ideas and methods directly use formulas, and complex problems are modified with formulas.

There are 248 apricot and peach trees in the orchard of 1. There are three times as many peach trees as apricot trees. How many apricot and peach trees are there?

How many apricot trees are there? 248 ÷ (3+ 1) = 62 (tree)

(2) How many peach trees are there? 62× 3 = 186 (tree)

A: There are 62 apricot trees and 86 peach trees/kloc-0.

Example 2 The east and west warehouses have a grain storage capacity of 480 tons, and the grain storage capacity of the east warehouse is 1.4 times that of the west warehouse. How many tons of grain are stored in each warehouse?

Solution (1) Grain quantity in stock in western China = 480 ÷ (1.4+ 1) = 200 (ton)

(2) Grain in stock in East China = 480-200 = 280 (ton)

A: There are 280 tons of grain in the east and 200 tons in the west.

There are 52 cars in Station 3a and 32 cars in bilibili. If there are 28 cars from Station A to bilibili and 24 cars from bilibili to Station A every day, the number of cars in bilibili will be twice that of Station A in a few days.

There are 28 cars from Station A to bilibili and 24 cars from bilibili to Station A every day, which is equivalent to 28-24 cars from Station A to bilibili every day. After a few days, the number of vehicles at Station A was regarded as 1 time. At this time, the number of vehicles in bilibili is twice, and the total number of vehicles in two stations (52+32) is equivalent to (2+ 1) times. Then, a few days later, the number of vehicles at Station A was reduced to (52+32) ÷ (2+65438).

The required number of days is (52-28) ÷ (28-24) = 6 (days).

A: After 6 days, the number of vehicles in bilibili is twice that of Station A. ..

Example 4 The sum of the three numbers A, B and C is 170, B is 2 times smaller than A, 4 times larger than A, and C is 3 times larger than A. What are these three numbers?

The numbers of solutions B and C are directly related to the number A, so the number A is taken as 1 time.

Because b is 2 times less than a by 4, if b is added by 4, the number of b becomes 2 times that of a;

And because C is three times more than A, the number of C minus 6 becomes three times that of A;

At this time, (170+4-6) is equivalent to (1+2+3) times. So,

A number = (170+4-6) ÷ (1+2+3) = 28.

B Quantity = 28× 2-4 = 52

C = 28× 3+6 = 90

A: The number A is 28, the number B is 52 and the number C is 90.