One person can do a certain job in twenty-one minutes, and another person can do the same job in twenty-eight minutes. How many
2 answers:
Answer: 12 min
Step-by-step explanation:
Given: Time taken by one person to do a job = 21 minutes
Time taken by another person to do a the same job = 28 minutes
If they work together then the total time taken by both of them to complete the job is given by :-
Hence, they will take 12 minutes to do the job together.
You might be interested in
Answer:
The specific gravity of kerosene is 0.82
Step-by-step explanation:
Let
x -----> the weight in grams of a cubic centimeter of Kerosene
y ----> the weight in grams of a cubic centimeter of water
z ---> the specific gravity of a substance
so
we have
substitute the values
Image is missing, so i have attached it
Answer:
21.07 mm²
Step-by-step explanation:
We will use the Formulas:
Area of semicircle = πr²/2
Area_rectangle = Length x width = Lw
We are given:
Length of rectangle = 14 mm
From the attached image, the diameter of the semicircle is equal to the length of the rectangle.
Thus;
diameter of semicircle = length of rectangle
Therefore,
diameter of semicircle = 14 mm
Also, from the attached image, the radius of the semicircle is equal to the width of the rectangle.
Thus;
diameter of semicircle/2 = radius of semicircle
Hence;
radius of semicircle = 14/2 = 7mm = width of rectangle
Thus;
Area of rectangle = L*w = 14 × 7 = 98 mm²
Area of semicircle = πr²/2 = π×7²/2 = 76.93 mm²
To get the area of the shaded region, we will subtract area of the semi-circle from the area of the rectangle.
Area of shaded region = Area_rectangle - Area_semicircle = 98 - 76.93 = 21.07 mm²
