1.3/4 of right angle is 3/4*90=67.5
2.5/4 of right angle is 5/4*90=112.5
3.5/3 of right angle is 5/3*90=150
4.2/3 of right angle is 2/3*90=60
Multiply both sides by 3 to get:
3r = sqrt(A)
Square both sides:
9r^2 = A
We are asked in this problem the surface area of the prism given the dimensions: <span>9mm by 12mm by 8mm. Surface area is the sum of the areas of each face of the prism. The formula for surface area is 2*lw+2*lh+ 2*wh. In this case, upon substitution, SA = 2*9*12+2*9*8+2*12*8 equal to a total of 552 mm2. </span>
Answer:
The percentage increase in bird population in the second years is 4% .
Step-by-step explanation:
Given as :
During two years, the population of birds of an island became 7 times more than before.
The the percentage increase in first year = =
=40%
Let The percentage increase in second year =
= r%
So, According to question
The initial population of bird = x
The increase population of bird =7 times before = 7 x
Now,
The increase population of bird = initial population of bird × (1+
) × (1+
)
Or, 7 x = x × (1+
) × (1+
)
Or,
= 1.4 × (1+
)
Or, 7 = 1.4 × (1+
)
Or,
= (1+
)
Or, 5 = (1+
)
Or, (1+
) = 5
Or,
= 5 - 1
Or,
= 4
∴ r = 4 × 100
I.e r = 400
so, The percentage increase = r% = 4
Hence The percentage increase in bird population in the second years is 4% . Answer