Solution
David answered on
Dec 26 2021
Ans. 1
The given function
2( ) 4 6f x x x
Now, replace xby 2 in the above equation,
2( 2) ( 2) 4 ( 2) 6
( 2) 4 8 6
( 2) 18
f
f
f
Option (b) is co
ect.
Ans. 2
Let xnumber of grapefruit juice added,
Initially the 30 cups have 8% ,
After mixing of x ,
Total amount of mixture,
30 x
So comparing the initial and final stage,
10 8
(30 ) 30
100 100
3 0.1 2.4
2
3
x x
x x
x
Hence, option (a) is co
ect.
Ans. 3
The given linear equations,
2 5
3 5 10
2 7 2
x y z
x y z
x y z
Put the value of z in the equation,
1,
2
y
x
Hence, option (d) is co
ect.
Ans. 4
The given functions,
2 2( ) 1, ( ) 2 1f x x g x x
Calculate the value of (1) (1)f g ,
Substitute the values of x in the above both equations and subtract them,
(1) 2, (1) 3
(1) (1) 2 ( 3) 5
f g
f g
Hence, option (a) is co
ect.
Ans. 5
The given points, (2, 1),( 5, 2) ,
The equation for line which passes through two points,
1 1( )y y m x x
Here, m is slope,
2 1
2 1
2 1 1
5 2 7
y y
m
x x
So, the equation,
1
1 ( 2)
7
1 9
7 7
y x
y x
Hence, option (d) is co
ect.
Ans. 6
The total cost of face cream mixture,
70 4 30 15 730$
The cost of one OZ of mixture of cream, as 730$cost is of 100OZcream,
730
1OZ 7.3$
100
Hence, option (b) is co
ect.
Ans. 7
Let, the unit digit is y and tense digit is x ,
So the desired number will be,
10x y
Also,
1 4
4 1 .......(1)
y x
x y
Now, reversing the digits,
10 10 63
9 9 63
7 ..........(2)
y x x y
y x
y x
Now, from the equation (1) and (2)
2, 9x y
Hence the number is, 29 and the option (c) is co
ect.
Ans. 8
The given inequalities,
2 3 8,2 3 9x x
The solution set for the inequality,
So the function lies in : 2 3x...