X = - 1/2
In other way is x = -0.2 , x = -5^-1
Answer:
A1) 125
A2) 47.5%
B) 30
Step-by-step explanation:
Remember 'of' in this sentence means times(*). % shows a certain number/100.
a1) 48% 'of' what number is 60?
(let unknown number be x)
48/100 *x=60
Solve the equation, and the answer is x=125
a2) what percentage 'of' 120 is 57?
(let the unknown percentage be x)
(x/100)*120=57
x=47.5%
b) 24 students= 80% of the total number of students
1%=24/80
100% of the total number of students=30
So, there are total of 30 students
Answer:
three u's and an I
Step-by-step explanation:
3×3=9
that's 3 u's so if you add an I its 10
Answer:
- train: 40 kph
- plane: 140 kph
Step-by-step explanation:
Let t represent the speed of the train in km/h. Then 4t-20 is the speed of the plane. Travel times are the same, so we can use the formula ...
time = distance/speed
and equate the travel times.
110/t = 385/(4t-20)
Cross multiplying gives ...
110(4t -20) = 385t
440t -2200 = 385t . . . . . eliminate parentheses
55t -2200 = 0 . . . . . . . . . subtract 385t
t -40 = 0 . . . . . . . . . divide by 55
t = 40 . . . . . . . . . . . add 40; train's speed is 40 kph
4t -20 = 140 . . . . . . find plane's speed; 140 kph
The train's speed is 40 km/h; the plane's speed is 140 km/h.
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<em>Check</em>
Train's travel time = 110 km/(40 km/h) = 2.75 h.
Plane's travel time = 385 km/(140 km/h) = 2.75 h.
