Question
Outer diameter of 20 cm long pipe is 25 cm. If the
thickness of the metal in the pipe is 1 cm. Find the total surface area of the pipe?Solution
Outer part surface area = 2(22/7)Rh Inner part surface area = 2(22/7)rh Area of shaded portion = 2 (22/7) R² - ((22/7) r)² = (22/7) (R² - r²) Total surface area = 2(22/7)Rh + 2(22/7)rh + 2(22/7) (R² - r²) = 2 (22/7) (R+r) [h + R - r] = 2 (22/7) (R+r) [h + thickness] Required surface area = 2 × 22/7 (R+r) [h + thickness] = 2 × 22/7 × (12.5 + 11.5) × 21 = 132 × 24 = 3168
The ratio of roots of the equation mx2 + nx + n = 0 is α/ β = a/b, then find the value of `sqrt(a/b)+sqrt(b/a)+sqrt(n/m)`
For which value of m, there is no solution to the equation -
a – b = 5
ma – 4b = 1
Find the area between the lines 18x +12y = 108, 9x  + 6y  = 27, x - axis and y -axis.Â
If x - √3 y = 8 Find the slope in angle?
If (5√P - 7√Q) = 5, [1.5P = 4Q-(R/3)+9] and (√P/√Q) = 1.6, then find out the value of ‘R’.
I. 2p2 + 5p + 2 = 0Â Â Â Â Â Â Â Â II. 2q2 + 11 q + 14 = 0
I. p2 – 5p + 6 = 0                 Â
II. 36q2 = 81
...The length of a line segment A, B is 10 units. The coordinates of point A are(2,3) and the value of ordinate of point B is 5. Then find the value of abs...
The equations 6x + my + 18 = 0 and 9x + 21y + 27 = 0 have a unique solution. Which of the following statements is definitely true?
I. p² - 365 = 364
II. q - √ 529 = √ 169
