The length of a room is 2 times it's breadth and 5 times of it's height.If the volume of the room is 800 m cube find the cost of papering it's wall at rs 6 per m²
Answer:
Rs. 1440
Step-by-step explanation:
Given that:
Breadth = b
Length = 2b
Height = 2b/5
Volume = b * 2b * 2b/5
Volume = 800 m³
800 = b * 2b * 2b/5
800 * 5 = 4b³
4000 = 4b³
4000/4 = 4b³/4
1000 = b³
10³ = b³
b = 10m
Length = 2 * 10 = 20m
Height = (2 * 10) / 5 = 4m
If plastering is at Rs. 6 per m²
Surface area:
2(lenght + breadth) height
2(20 + 10)4
2(30)4 = 240m²
Rs. 6 * 240 = Rs. 1440
X=one type that cost 9
y=one type that cost 8
total books=type1+type2
total books=13
x+y=13
the total cost=cost of each added together
cost of each=number of books times cost per book
total cost=108
9x+8y=108
we have
x+y=13
9x+8y=108
solve for x and y
multiply first equation by -8 and add to first equation
-8x-8y=-104
<u>9x+8y=108 +</u>
x+0y=4
x=4
subsitute
x+y=13
4+y=13
minus 4
y=9
4 of the $9
9 of the $8
thats how to solve
Answer:
Missing same value is 0.02
Step-by-step explanation:
Instead of multiplying big decimal numbers we put short cut by making 0.98 as a difference of near integer and one decimal.
i.e 0.98 =1-0.02
Since 0.02 is the same for other also other term
0.73 = 0.75-0.02
Now product can be done very easily.
Steps are shown below:
0.98x0.73
= (1-0.02) (0.75-0.02)
= 0.75 -0.02(1+0.75)+0.0004
= 0.7504-(0.035)
= 0.7154
=0.44
Answer:
C)
f(–3) = 9
Step-by-step explanation:
Given f(x) = 4x^4 + 5x^3 – 15x^2 – 45
f(-3) means let x = -3
f(-3) = 4(-3)^4 +5(-3)^3 – 15(-3)^2 – 45
=4(81) +5(-27) -15(9) -45
= 324 - 135 - 135 -45
=9
