Question
Find the fourth proportion of (3k - 5), (6k - 10) and
(9k - 15). (Note: 'k' is the largest single-digit prime number.)Solution
'k' = 7 3k - 5 = 3 × 7 - 5 = 16 6k - 10 = 6 × 7 - 10 = 32 9k - 15 = 9 × 7 - 15 = 48 Let the fourth proportion be 'm'. 16 : 32 :: 48 : m So, 16 × m = 32 × 48 Or, 'm' = 96
If b sin θ = a, then sec θ + tan θ = ?

In a triangle ABC, D, E and F are the mid-points of the sides BD, CA and AB, respectively. BE and DF intersect at X. DE and CF intersect at Y. Find XY = ?
If the area of a triangle is 1690 cm2 and base: corresponding altitude is 4:5, then the altitude of the triangle is:
The perimeter of a square is the same as that of a rectangle with length 18 cm and width 10 cm. What will be the circumference of a semicircle whose rad...
A rectangular plot has an area of 490 m². If the length of the rectangular plot is 24.5 m. Find the perimeter of the rectangular plot.
A rectangular park measuring 24 metres by 18 metres is set to have a 2-metre-wide path constructed along its interior perimeter. The cost of constructio...
A rectangular ground is 65 metre long and 45 metre broad. If two 10 metre wide paths one parallel to the breadth and one parallel to the length, of the�...
The average cost of two chairs is Rs. 15000. The average cost decrease by 30% when one more chair is included. What is the cost price of the 3 rd <...
If the curved surface area and the radius of a cylinder are 440 cm2 and 7 cm, respectively, then find the volume (in cm3) of the c...
A circular field, which covers an area of 1386 square meters, is planned to be enclosed by a compound wall that rises to a height of 3 meters. The wall ...