Question

`{:(,"Column A",,"Column B"),(12.,"If the area of a square field is 25 hectsares, then the sum of the length of the diagonals is _____.",(a),220),(13.,"A playgraound is in the shape of a rhombus whose diagonals are 10 m and 15 m. The costof levelling it at the of leelling it at the rate of Rs 12 per" m^(2) "is Rs. _____.",(b),1000),(14., "The volume of a cube of edge 10 cm in " cm^(3) "is _____.",(c ),900),(15.,"The length of the arc of a sector with angle" 60^(@) "and radius 210 cm is ______.",(d),1000sqrt(2)),(,,(e ),3000),(,,(f),500sqrt(2)):}`

Answer 1

Correct Answer - D
12. Option (d): Area of the square = 25 hectares = 250.000 `m^(2)`.
Let a be the side of the square.
`rArr a^(2)=250,000 rArr a = sqrt(250,000)=500`
a = 500 m
Length of the diagnoal = `sqrt2xxa`
`=500sqrt2`
Sum of the lengths of the diagonals
`=500sqrt2+500sqrt2=1000sqrt2m`
13. Option (c): Area of the playground `=(1)/(3)xx10xx15`
`=75m^(2)`
`therefore" The cost of levelling "=75xx12=Rs.900`
14. Option (b) : Volume of a cube of edge, 10 cm = 1000 `cm^(3)`
15. Option (a) : Length of the arc of a sector
`=(theta^(@))/(360^(@))xx2pir`
`=(60^(@))/(360^(@))xx2(22)/(7)xx210`
`=(1)/(6)xx2xx(22)/(7)xx210`
220 cm