Question

10. A rectangular strip 25 cm x 7 cm is rotated about the longer side. Find the whole surface of the solid that
is generated.​

Answer 1

Step-by-step explanation:

Perimeter of trapezium = 104 m

Length of Non-parallel sides = 18 m and 22 m

Altitude = 16m

Area of Trapezium = 0.5 * (sum of parallel sides)*altitude ------ (1)

Sum of parallel sides = Perimeter - (sum of non-parallel sides) = 104 m - (18+22)m = 104-40 m = 64 m

From (1), Area of Trapezium = 0.5*64*16 = 512 m^2

Ans: Area of trapezium = 512 m^2

Answer 2

Step-by-step explanation:

25 x 7 + 25 x 7

= 175 + 175

= 350cm²