Subject :IMO Class : Class 4
Komal wants to decorate the boundary of a rectangular design with lace. If she uses 48 cm length of lace costing Rs 15 per cm, then which are the possible dimensions of design and total cost of lace?
A l = 16 cm, b = 8 cm and Rs 1920
B l = 8 cm, b = 4 cm and Rs 720
C l = 4 cm, b = 8 cm and Rs 620
D l = 16 cm, b = 8 cm and Rs 720
ANSWER IS D
Ans 1:
Class : Class 6
Answer is D Total length of lace = 48 cm = Perimeter of rectangle 48 = 2 ( l b ) l b = 24cm Cost per cm = Rs. 15 Cost of 48 cm = 48 x 15 = Rs.720 When l = 16 cm and b = 8 cm P = 2 ( 8 16 ) = 2 (24) = 48 cm
Ans 2:
Class : Class 6
ANSWER IS D
Ans 3:
Class : Class 9
D