these 3 question
plus steps
and i will mark them who guves the 3 answers
AS A BRAINLIEST LOL
Answers
Answer: Area of All walls, ceilings and floor `= 2(lb + lh + bh)`
`= 2(15 xx 10 + 15 xx 7 + 10 xx 7)`
`= 2(150 + 105 + 70)`
`= 2 xx 325 = 650`
Area of Floor `= 15 xx 10 = 150`
Hence, Painted Area `=650-150=500`
As, one can of paint is enough for 100 sq m
So, `(500)/(100) = 5` cans are needed to paint the hall.
Alternate Method: Area of Walls of a Room `= 2 xx \h \xx (l + b)`
`= 2 xx 7 xx (15 + 10)`
`= 14 xx 25 = 350`
Area of Roof = Area of Floor = 150
Total Area to be painted `= 350+150=500`
Question 6:
Answer:
Similarity: Their dimensions are equal
Difference: The figure on the left is cylindrical and that on the right is cuboidal.
Curved surface area of cylinder `=2πrh`
`=2xx(22)/(7)xx7/2xx7`
`=22xx7=154` sq cm
Surface area of cube `=4xx\text(Side)^2`
`=4xx7^2=4xx49=196` sq cm
It is clear that the cylinder is having a larger surface area.
Question 7:
Answer: Surface area of cylinder `=2πr(r+h)`
`=2xx(22)/(7)xx7xx(7+3)`
`=44xx10=440` sq m