Current location - Training Enrollment Network - Mathematics courses - Mathematics application problems in grade four
Mathematics application problems in grade four
(1) Wang is a professional breeder, raising 6 10 hens, which is more than 7 times that of 15 cocks. How many domestic cocks does Uncle Wang have?

Solution: Raising roosters: (6 10- 15)/7=85.

(2) In order to encourage residents to save water, the water supply company stipulates that if the monthly water consumption of each household is within 12 tons (including 12 tons), it will be charged 1.2 yuan per ton, and if it exceeds 12 tons, it will be charged 5 yuan per ton. Wenwenjia paid 24.4 yuan for water last month. How many tons of water did Wenwenjia use last month?

Solution: Wenwenjia's water consumption last month: (24.4-12 *1.2)/5+12.

=2+ 12

= 14 ton

(3) The sum of five consecutive natural numbers is 75, with the largest being (17) and the smallest being (13).

(4) In an isosceles triangle, the base angle is two degrees of the vertex angle, and the vertex angle is (180/5=36) degrees.

(5) Triangle, one angle is 25 degrees, another angle is twice as large as it, and the third angle is (105) degrees, which is an (obtuse) triangle.

(6) When a number is multiplied (a number greater than 1), the product must be greater than this number. When a number is divided by (a number less than 1), the quotient must be greater than this number.

7. An airplane flies at a speed of 450 km/h for 3.25 hours to reach its destination. When returning, the speed is 38 km/h slower than before. How many hours does it take to get back to the original place? The answer is reserved to two decimal places.

Solution: Go back to the original place:

450 * 3.25/(450-38) =1462.5/412 = 3.55 hours.

8. The degree of Angle A is three times that of Angle B, and the sum of the degrees of Angle A and Angle B is 136. What's the difference between the degrees of Angle A and Angle B? Solve by equation.

Solution: Let angle B be x degrees, then angle A is 3x degrees, and the difference between the degrees of angle A and angle B is 3x-x, then:

x+3x= 136

X=34 degrees

That is to say, the degree difference between angle A and angle B is 3x-x=3*34-34=68 degrees.