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The two trains run in opposite directions from 580 kilometers away and meet after 5 hours. The speed ratio of the two trains is 14:15 The speed ratio of adding one or two trains all the time is 14:15. How many kilometers do the two trains travel per hour?
580 △ 5 = 116 (km)
116 × 14 / 29 = 56 (km) a
116 × 15 / 29 = 60 (km) B
(1) The average number of a, B and C is 60. The ratio of a, B and C is 3:2:1. What are the numbers of a, B and C?
(2) Oranges from the fruit wholesale department are 120 kg less than apples. It is known that oranges weigh two fifths of apples. How many kg are oranges and apples?
(3) The perimeter of a right triangle is 36 cm, and the length ratio of the three sides is 3:4:5. How many square centimeters is the area of the triangle?
Please list the formula and explain
1, a 30, B 20, C 10, 60 in total, the proportion of the three can be calculated,
The orange is three fifths less than the apple, so the orange juice is 80 and the apple is 200
The length of the three sides of the triangle is 9, 12, 15 and 15 respectively, which must be hypotenuse, and the area is 9 × 12 △ 2
A and B two cars respectively from AB two opposite, a car 54km per hour, two cars from the midpoint 18km meet. AB two distance is how many km?
Need a solution
The two vehicles of Party A and Party B run from AB to ab respectively. Car a runs 42km per hour, while car B runs 54km per hour. The two vehicles meet at 18km away from the midpoint. What is the distance between a and B?
There is no solution to this problem
Is the square of the sum of the first two digits and the last two digits of a four digit number exactly equal to the four digit number?
A435 B8775 C2025
X = 1000A ＋ 100A ＋ 10B ＋ B = 11 (100a ＋ b), where 0 ＜ a ≤ 9, 0 ≤ B ≤ 9. It can be seen that the square number x is divisible by 11, so x is divisible by 112. Therefore, the number 100A ＋ B = 99A ＋ (a ＋ B) can be divisible by 11, so a ＋ B can be divisible by 11
The distance between a and B is 6cm on the map with scale of 1:5000000. On the other map with scale of 1:6000000, the distance between a and B is 1:5000000
Brother, the question is not complete. Do you want to ask how far away a is from B on the 1:6000000 map? If so, let me tell you the method: let a be a and X on the 1:6000000 map, then on the two maps, a = 6 × 5000000 = x × 6000000, then the solution is x = 5cm
Mathematical Cauchy inequality
a. B is greater than 0, a + B = 1, prove that the square of (a + 1 / a) + (B + 1 / b) is greater than or equal to 25 / 2~
It is proved that: (1) from the proposition and Cauchy inequality, (1 & sup2; + 1 & sup2;) [(a + 1 / a) & sup2; + (B + 1 / b) & sup2;] ≥ [(a + 1 / a) + (B + 1 / B)] & sup2; = [1 + 1 / A + 1 / b] & sup2;; (2) from the proposition a + B = 1 and Cauchy inequality, (1 / A + 1 / b) = (a + b) (1 / A + 1 / b) ≥ (1 + 1) & sup2; =
There are six tons of coal in a canteen. If you burn one sixth of a ton of coal every day, how much coal can you burn
A canteen has six tons of coal. If you burn one sixth of a ton of coal every day, this pile of coal can be burned for 36 days
Ask: a problem of seeking the maximum of basic inequality?
If x = 2 radical XY, X and y are required to be positive numbers, then what should we do when x and y are negative numbers
-X is a positive number, f (x) = - [12 / (- x) + 3 (- x)], only the minimum value in is required
The two cars left from two places 360 kilometers apart at the same time and met 2.4 hours later. It is known that the speed ratio of fast train to slow train is 14:11
How many kilometers per hour is the express?
The fast train speed is 14x km / h, and the slow train speed is 11x km / h
2.4（14x+11x）=360
So x = 6
So the fast train is 84km / h and the slow train is 66km / h
Solve the inequality system X-1 / 2 + 3 is greater than or equal to x + 1, 1-3 (x-1) is less than 8-x, and write the integer solution of the inequality system
X-1 / 2 + 3 is greater than or equal to x + 1
x-1/2+3 >=x+1,、
x-1+6>=2x+2
x-2
The solution of inequality system is - 2
RELATED INFORMATIONS
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