Question

please please answer all of them  

1. The lateral area of a cone is 49 in² with a slant height of 7 in. Then the radius is _____ in. Round answers to the nearest tenth.

2. The surface area of a cone with a radius of 3.3 cm and slant height of 5 cm is _____ cm ². Round answers to the nearest tenth.

3. The surface area of a cone is 18.6 in² with a radius of 1.2 in. Then the slant height is _____ in. Round answers to the nearest tenth.

4. The area of just the sides of a solid is called the _______.

a.		lateral area
b.		none of these
c.		volume
		d. surface area

Answer 1

Solution:

1.

The lateral area of a cone is 49 in2 with a slant height of 7 in

As we know that

The lateral area of a cone = ? r l

where r is radius and l is slant height

The lateral area of a cone = ? r l = 49

r = 49 /? l

r = 49/ (22*7/7 ) = 49/22

the radius is 2.23 in  

2. The surface area of a cone with a radius of 3.3 cm and slant height of 5 cm is = ? r l + ? r²

= 3.14 * 5*3.3 + 3.14 * 3.3²

= 51.81 +34.19  

=86.00 cm^2

3.

The surface area of a cone is 18.6 in2 with a radius of 1.2 in

using formula

? r l + ? r² = 18.6

3.14 *1.2 * l + 3.14* 1.2² = 18.6

l = 14.0874/(3.14*1.2) = 3.74 in

the slant height is 3.74 n.

4.  The area of just the sides of a solid is called the

(a) Lateral area