[tex]koi \: bhi \: noi \: h \: kya[/tex]


= 182 x 22/7 = 26 x 22 = 572 cm?
– A toy is in the form of a

2 thoughts on “<br />[tex]koi \: bhi \: noi \: h \: kya[/tex]<br /><br /><br />= 182 x 22/7 = 26 x 22 = 572 cm?<br />– A toy is in the form of a”

1. 214.5 cm²

   Step-by-step explanation:

   Given:

   ➜ A toy is in the form of a cone of radius 3.5 cm mounted on a hemisphere of same radius. The total height of the toy is 15.5 cm.

   Find:

   ➜ Find the total surface area of the toy.

   According to the given question:

   ➜ 3.5 cm = radius of the cone and the hemisphere.

   ➜ 15.5 cm = total height of the toy.

   ➜ 12 cm = height of the cone = (3.5 – 15.5 = 12cm).

   Calculations:

   ➜ Slant height of cone (I) = √h² + r²

   ➜ I = √12² + (3.5)²

   ➜ I = √12² + (7/2)²

   ➜ I = √144 + 49/4 = √(576 + 49)/4 = √625/4

   ➜ I = 25/2

   Formulas:

   πrl is curved surface area of cone.

   2πr2 is the curved surface area of the hemisphere.

   ➜ (22/7 × 7/2 × 25/2) = 275/2 cm²

   ➜ 2 × 22/7 × (7/2)

   ➜ 2 77 cm²

   Formula:

   Total surface area of toy = Curved Surface Area of cone + Curved Surface Area of hemisphere.

   ➜ (275/2 + 77) cm²

   ➜ (275 + 154)/2 cm²

   ➜ 429/2 cm²

   ➜ 214.5 cm²

   Therefore, 214.5 cm² is the total surface area of the toy.

   Reply

2. Answer:

   214.5cm²

   Step-by-step explanation:

   Total surface area of toy = Curved surface area of cone + surface area of hemisphere

   Curved surface area of cone = πrl

   => Where r = 3.5cm,

   => Height = 15.5 − 3.5 = 12cm

   And hence, l=12.5cm(by using formula l²=h²+b²)

   Therefore C.S.A. of cone = π×3.5×12.5

   = 137.5cm²

   Surface area of hemisphere =2πr²

   =2×π×(3.5)²

   =77cm²

   Hence T.S.A of toy = 77+137.5

   = 214.5cm²

   Reply