Two times of a number is 4.56 more than half of it

Two times of a number is 4.56 more than half of it

2X-X/2＝4.56
2X=1/2X+4.56
Let this number be x, then the equation can be listed
2x=0.5x+4.56
The result is x = 3.04
In other words, the original problem is: a number plus three times more than 4.56, 4.56/3 = 1.52 and multiply by 2
The distance between a and B is 400km. A bus from a to B runs 68km per hour and 28km per hour
Help younger brother, 5555, better take explanation
The distance between a and B is 400km. A bus runs 68 kilometers per hour from place a to place B. after the bus runs 28 kilometers, a truck runs 56 kilometers per hour from place B to place a. How many hours after the truck leaves, the two cars meet?
Let the two trucks meet after X hours
The truck has traveled 56x kilometers
The bus has traveled (68x + 28) km
56X+68X+28=400
X = 3 hours
Speed sum of passenger car and freight car = 68 + 56 = 124 km / h
It takes (400-28) / 124 = 372 / 124 = 3 hours to meet
Let a vector = (4cos α, sin α), B vector = (sin β, 4cos β), if Tan α, Tan β = 16, prove that vector a is parallel to vector B
If vector a is parallel to vector B, then it is equivalent to 4cos α * 4cos β - sin α * sin β = 0
Divide the equation by cos α * cos β to get 16 Tan α Tan β = 0
So tan α Tan β = 16
The above steps are reversible
A number minus 20% of it is equal to 56?
I need it tomorrow
56÷（1-20%）=70
The distance between a and B is 400km. A car drives from a to B at the speed of 80km / h. what is the functional relationship between the distance s and time t?
s=400-80t
s=400-80t
S = 400-80t note: t unit is hour
Four large trucks transport sand and soil, and seven times transport 336 tons of sand and soil. Now there are 420 tons of sand and soil, and five times transport is required. Q: the same trucks need to be added______ A car
1 truck 1 time transport sand: 336 △ 4 △ 7 = 12 (tons), 5 times transport 420 tons of sand: 420 △ 12 △ 5 = 7 (vehicles). Need to increase 7-4 = 3 (vehicles). Answer: need to increase the same truck 3. So the answer is: 3
Stretch out your left hand, count from the thumb, count back to the little finger, and repeat the count in turn like this
Start with the thumb and count nine times
So 2003 / 9 = 222 Five
It's little finger
The distance between a and B is 400km. A car has traveled 160km from a to B in the first two hours. At this speed, how much time will it take to reach B?
To solve by proportion
Set X hours to arrive
160：2=（400-160）：x
X = 3 hours
3 hours
It takes x hours, 400 / (x + 2) = 160 / 2, x = 3
Three large trucks are used to transport sand and gravel. A total of 240 tons of sand and gravel are transported in five trips. Now 400 tons of sand and gravel are transported. It is required to add the same trucks after five trips
400÷（240÷3÷5）÷5-3
=400÷16÷5-3
=5-3
=2
Count the numbers from your thumb, 1, 2, 3 Count the little finger to 5, then count the ring finger to 6, the middle finger to 7, the index finger to 8, the thumb to 9, then count the index finger to 10 May I ask: what is the number from the nth to the middle finger?
The first number to the middle finger is 3 3 = 4 * 1-1
The second number to the middle finger is 7 7 = 4 * 2-1
The median number is from 3 to 11
The fourth number to the middle finger is 15 15 = 4 * 4-1
.
The nth number to the middle finger is 4N-1
1 2 3 4 5
9 8 7 6
one thousand and eleven
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