Advertisements
Advertisements
प्रश्न
The cost of levelling the ground in the form of a triangle having the sides 51 m, 37 m and 20 m at the rate of Rs 3 per m2 is Rs 918.
विकल्प
True
False
उत्तर
This statement is True.
Explanation:
a = 51, b = 37, c = 20
`s = (a + b + c)/2`
⇒ `s = (51 + 37 + 20)/2 = 108/2 = 54`.
Area (Δ) = `sqrt(s(s - a)(s - b)(s - c))`
⇒ Area (Δ) = `sqrt(54(54 - 51)(54 - 37)(54 - 20))`
⇒ Area (Δ) = `sqrt(54 xx 3 xx 17 xx 34)`
⇒ Area (Δ) = 306 m2
Cost of painting = Area (Δ) × Cost per m2
⇒ Cost of painting = 306 × 3 = Rs. 918
APPEARS IN
संबंधित प्रश्न
A traffic signal board, indicating ‘SCHOOL AHEAD’, is an equilateral triangle with side ‘a’. Find the area of the signal board, using Heron’s formula. If its perimeter is 180 cm, what will be the area of the signal board?
There is a slide in the park. One of its side walls has been painted in some colour with a message “KEEP THE PARK GREEN AND CLEAN” (see the given figure). If the sides of the wall are 15m, 11m, and 6m, find the area painted in colour.
Find the area of a triangle whose base and altitude are 5 cm and 4 cm respectively.
Some measures are given in the adjacent figure, find the area of ☐ABCD.
Find the area of the triangle formed by the points
(–10, –4), (–8, –1) and (–3, –5)
The perimeter of an equilateral triangle is 30 cm. The area is
The area of the isosceles triangle is `5/4 sqrt(11)` cm2, if the perimeter is 11 cm and the base is 5 cm.
If the side of a rhombus is 10 cm and one diagonal is 16 cm, the area of the rhombus is 96 cm2.
In the following figure, ∆ABC has sides AB = 7.5 cm, AC = 6.5 cm and BC = 7 cm. On base BC a parallelogram DBCE of same area as that of ∆ABC is constructed. Find the height DF of the parallelogram.
A design is made on a rectangular tile of dimensions 50 cm × 70 cm as shown in the following figure. The design shows 8 triangles, each of sides 26 cm, 17 cm and 25 cm. Find the total area of the design and the remaining area of the tile.
