60 minutes is 20% of 300 minutes
hope i helped
<h3><u>Answer:- </u></h3>


<h3><u>Solution</u> :-</h3>

The unit of mass is kg and unit of Volume is m³ . Since density is division of mass by volume , the corresponding units will also get divided and unit of density would come out to be kg/m³
<u>Some basic </u><u>derived </u><u>Units :- </u>
- area => m²
- volume cubic meter => m3
- speed meter per second => m/s
- acceleration => m/s²
- mass density meter => kg/m3
- specific volume cubic meter per kilogram m³/kg
Answer:
let the unit digit be x
and the tens digit be y
so x+y = 9 ---> y = 9-x
the number is 10y+x
the number reversed is 10x + y
3(10y+x) = 8(10x + y)
30y + 3x = 80x + 8y
22y = 77x
2y = 7x
2(9-x) = 7x
18 - 2x = 7x
18=9x
x=2
y=7
the number is 72
check:
number is 72
reverse is 27
is 3(72) = 8(27)
Answer:

Step-by-step explanation:





Use subtitution method to solve the problem.
First, change y to the value of x in order to find the exact value of x.
x + y = 4
y = 4 - x
Second, subtitute y with 4 - x from the first equation
y = -x² + 2x + 4
4 - x = -x² + 2x + 4
move all terms to the left side
x² - 2x - x + 4 - 4 = 0
x² - 3x = 0
x(x - 3) = 0
x = 0 or x = 3
Third, now we have 2 values of x. Find the value of y for each of x
For x = 0
y = 4 - x
y = 4 - 0
y = 4
For x = 3
y = 4 - x
y = 4 - 3
y = 1
The solution is (0,4) and (3,1). The answer is option b