81 degrees
1 degree = 2 pi / 360
81 degrees = 162 pi / 360
=9 pi / 20
L (arc) = radius x angle
= 10 x 9 pi / 20
90 pi /20
9/2 pi : D
The answer is D
Equation x y = -4y implies x=-4
Replacing the value of x in the following equation:
-4y = 2(-4)-1 implies y = 9/4 = 2.25
Function A because in one hour it gets up by 4 but in function B it gets up by only 2
First, let us define our variables.
Let
x = age of the father
y = age of the son
z = age of the daughter
5 years ago..
(x – 5) = age of the father
(y – 5) = age of the son
(z – 5) = age of the daughter
After 18 years...
(x + 18) = age of the father
(y + 18) = age of the son
(z +18) = age of the daughter
From the first condition
y = z + 5 à
eqn 1
5 years ago
(x-5) = 23 + (y-5) + (z-5)
x –y –z = 18 à
eqn 2
after 18 years
(x+18) = 17*[(y +18 –z – 18)]
x – 17y + 17z = -18 à
eqn 3
solving the 3 equations simultaneously
x = 67
y = 27
z = 22
If the number before the place you are rounding to is a 5 or more you round up but if it is a 4 or below it stays the same so the answer is 28,000,000
