A car from a city to B city, 4 / 5 hours, 3 / 10 of the whole journey. According to this calculation, how many parts of the journey can I travel in 4 / 5 hours?

1 / 10 / 4 / 5) = 1 / 3 / 8 = 8 / 3 hours

Rational number AB satisfies a > B.B

From the meaning of the title, we can get the conclusion
a>0>b
|a|-a>b

Some aircraft carriers are equipped with ejection systems to help the aircraft take off. It is known that the maximum acceleration that a certain type of fighter can produce when accelerating on the runway is 5m / S2. When the aircraft's speed reaches 50M / s, it can leave the aircraft carrier and take off. Suppose the aircraft carrier is in a static state, question: (1) if the aircraft is required to taxi 160m and then take off, how much power must the ejection system make the aircraft have Initial velocity? (2) If the ejection system is not installed on a certain ship, the aircraft of this type is required to take off normally on this ship. How long is the ship at least?

(1) According to the velocity displacement common v2-v02 = 2aX, V0 = V2 − 2aX = 502 − 2 × 5 × 160m / S = 30m / S. (2) without ejection system, the initial velocity of the aircraft is 0, then from V2 = 2Al, l = v22a = 5022 × 5m = 250m

The sum of 40% and 8 of a number equals one fifth of it plus 20. Find the number

Let this number be X
40%x+8=1/5x+20
0.2x=12
x=60

How to make a paper bridge requires several newspapers and a small amount of transparent glue, which can carry 250 grams and the width of the bridge deck is more than 10 cm

The newspaper should be as strong as possible, fixed with transparent glue, and the bridge deck should be arched 250g, which is not a problem

Solve the equation 2x + 1 / 3-5x-1 / 6 = 1 1 / 7 (2x + 14) = 4-2x 3 / 10 (200 + x) - 2 / 10 (300-x) = 300 * (9 / 25)

2x+1/3-5x-1/6=1
-3x+1/6=1
-3x=5/6
x=-5/18
1/7（2x+14）=4-2x
2x+14=28-14x
16x=14
x=7/8
3/10（200+x）-2/10（300-x）=300*（9/25）
60+0.3x-60+0.2x=108
0.5x=108
x=216

The distance between a and B is 40 kilometers. A starts for 1.5 hours, B starts again, a is behind, B is in front, and both of them walk in the same direction. The speed of a is faster than that of B
The distance between a and B is 40 kilometers. A starts for 1.5 hours, B starts again, a is behind, B is in front, two people walk in the same direction, a's speed is 8 kilometers per hour, B's speed is 6 kilometers per hour, a few hours after starting to catch up with B?
Why do some people calculate 15.5 hours? Is the answer 15.5 or 14?

（40-8×1.5）÷（8-6）+1.5
=28÷2+1.5
=15.5 hours

1. Given the quadratic power of | a + 2 | + (B-1) = 0, find the quadratic power of 2A B-3 (the quadratic power of AB AB) + the quadratic power of 3AB
2. No matter what the number of X and Y is, 2 (the quadratic power of X, y + the quadratic power of XY) - [2 (the quadratic power of X, Y-1) + the quadratic power of 2XY] is the fixed value
3. Finding the difference between the quadratic power of integral x-7x-2 and the quadratic power of - 2x + 4x-1

1. It is known that the quadratic power of | a + 2 | + (B-1) is 0, the quadratic power of 2a is B-3 (the quadratic power of AB AB) + the quadratic power of 3AB is a + 2 = 0B-1 = 0  a = - 2, the quadratic power of 12a is B-3 (the quadratic power of AB AB) + the quadratic power of 3AB is 2A & # 178; b-3ab + 6ab & # 178; = 2 * 4 + 6-12 = 22, no matter what the number of X and Y is, the quadratic power of 2 (x) is y +

1+3+3+7+9+11+… +How to calculate 993 + 995 + 997 + 999 simply

Continuous odd addition
1 -- 999, a total of: (999-1) △ 2 + 1 = 500 odd numbers
1+3+5+7+9+...+999
=(1+999)×500÷2
=250000

The total weight of apples and pears from the fruit shop is 480KG, of which the weight of apples is three times that of pears? (solved by equation)

Suppose the pear has x kg, then the apple has 3x kg, x + 3x = 480 & nbsp; & nbsp; 4x = 480 & nbsp; & nbsp; & nbsp; X = 1203x = 3 × 120 = 360 A: the pear from the fruit shop has 120 kg, and the apple has 360 kg

A car from a city to B city, 4 / 5 hours, 3 / 10 of the whole journey. According to this calculation, how many parts of the journey can I travel in 4 / 5 hours?