Mathematical Ability Training (2)

Fill in the blanks:

1 and 28 consist of 1 and 28.

When the clock is 1: 45, the obtuse angle formed by the hour hand and the minute hand is degrees.

There is a rectangle in the picture on the right.

Someone wants to go to the building 15 floor. It takes him 100 seconds to get from the first floor to the fifth floor. If he continues to go up the 15 floor at this speed, it will take another second.

A two-digit number, the number in the tenth place is 3 less than the number in the fourth place, and the sum of the number in the tenth place and the number in the fourth place is this two-digit number, that is.

If a ÷ 2-b ÷ 5 = 0, then a: b =:.

Moving the decimal point of a decimal point to the right results in a number that is 7.2 higher than the original number. Then the original decimal point is.

Are you online? In a triangle, ∠ A = 2 ∠ C, ∠ B = 3 ∠ C, then ∠ C = degrees, and this triangle is a triangle.

There are three natural numbers, the ratio of A to B is 3: 5, the ratio of B to C is 4: 7, and the sum of the three numbers is 20 1, then A is.

The ratio of male to female employees in a factory is 2: 3, but after 36 new male employees are transferred, the ratio of male to female employees is 4: 5, and now there are fewer male employees than female employees.

True or false:

The price of a dress goes up first and then goes down. The current price of this dress is the same as the original price. ()

The height of the cylinder is constant, and the volume of the cylinder is proportional to the radius of the bottom circle. ()

Because the denominator of contains a prime factor of 3, it cannot be converted to a finite decimal. ? ()

The ratio of the degrees of the three internal angles of a triangle is 2: 3: 3, which is an isosceles triangle. ()

In the equation a-b=c, if A: B = 5: 2, then C must be A. ()

Multiple choice question:

A×a×a can also be written as? ()

a、3a？ b、3+a？ c、a+a+aD、a3

In a proportional formula, it is known that the sum product of two internal terms is, one external term is 0.2 and the other external term is ().

3C？ d、5

If the length of two adjacent sides of a rectangle increases, then the area of the obtained rectangle increases relative to the area of the original rectangle? ()

B, is it? C, is it? d、

A cube with a volume of 1 m3 can be sawed into small cubes with a volume of 1 cubic decimeter.

a、 100？ b、 1000C、 10000D、 1000000

From Changchun to Shenyang, it takes 4 hours for A train and 5 hours for B train. The speed ratio between A train and B train is ().

a、4:5B、5:4？ C, D,

Calculation problem:

Write the number directly.

0.5÷0.0 1=0.26×=×0. 1=? (20-)×5=

45÷×=? 10-2×==?

2. Solve the equation.

Calculate, what can be simplified should be simplified.

(2)

(4)

(5)

V. Graphic problems:

1. As shown in the figure, it is known that the area of a parallelogram is 320 square centimeters, so find the area of a trapezoid.

As shown in the figure, the circumference of the circle is 12.56 cm, and the area of the parallelogram ABCD is 2 1.6 cm. What is the area of triangle AOB?

3. Find the area of the shaded part. (Unit: cm)

Sixth, solve the problem.

1. The radius of a semicircular flower bed is 10 meter. How many pots of chrysanthemums does it need to put every 0.3 meters a week?

It takes 4 hours for the car to go from A to B, which is less than the time to come back. What is the speed ratio between going there and coming back?

There are two oil drums containing the same amount of oil. After the first barrel was used and the second barrel was used up to 40%, 8 kg of oil was taken out of the first barrel and poured into the second barrel. At this time, the ratio of the second barrel oil to the first barrel oil is 13: 14. How many kilograms of oil were originally contained in these two barrels?

A coach, passengers get off midway, 12 people get on. At this time, the ratio of the number of passengers on the bus to the original number of passengers on the bus is 13: 14. How many passengers are there in this bus?

5. In an earthquake, the earthquake center propagates both longitudinal and shear waves in all directions at the same time. The propagation speed of longitudinal wave is 3.96 km/s, and the propagation speed of shear wave is 2.58 km/s. After the earthquake, the seismic monitoring station receives the longitudinal wave of the earthquake with seismograph, and it takes 18.5 seconds to receive the shear wave of the earthquake. How many kilometers is the epicenter of this earthquake from the monitoring point? (accurate to one place)

Math Ability Test (6) Answers

1. 1, 18? 19? 202、 19.7? 3、3:4? 4、? 5、4.5? 67.5?

6、3:57、 180? 8、67.5? 9、? 10、6

Two. 1，√2，√3，X4，√

Third, 1, C2, d? 3、A4、C

4. 1，x= 12，x=3，( 1)？ (2)x=364、 1272 10

Verb (abbreviation of verb) 1, 58.875 square centimeters.

Six 1,? 2、

7. 1, (60×15+1800) ÷ (1-) = 9 (km).

2680 yuan

The first time B catches up with C is 30 ÷ (5-3) = 15 (seconds), and the second time B catches up with C is 90 ÷ (5-3) = 45 (seconds). The list is:15,60,105,6550.

As can be seen from the table, the three reptiles arrived at the same place for the first time from 60 seconds after departure, that is, 1 minute.

If the speed is increased by 20%, the original time will be 20% longer than it is now. Now the time used is 1÷20%, and the original time is 5+ 1 = 6 (hours). If the speed is advanced by 1 00km, the speed will be increased by 30%, and the time can be advanced by1hour. Now it needs 130% = (hours), and the original road section needs+1 = (hours), so the distance of the first section 100 km needs 6-= (hours), and the original speed is 100 ÷ = 60 (km/.

Football 40 yuan, Basketball 32 yuan 6? Suppose you need x kilograms of water. According to the meaning of the question:

X= 180。