Answer:

Step-by-step explanation:
The total surface area of a cone is given by :

Put r = 2r and l = 2l in the above formula

Hence, the total surface area of the cone is
.
Answer:Sara hina and Arslan Have RS79.4,RS 72.4 and RS238.2 respectively.
Step-by-step explanation:
Step 1
Let the amount that hina has be x
the amount that sara has be represented as 7+x
and the amount that Arslan have be represented as 3(7+x)
such that the total amount in their wallet which is 390 can be expressed as
x+7+x + 3(7+x)=390
Step 2
Solving
x+7+x +21+3x=390
5x+28=390
5x==390-28
x=362/5=72.4
Hina has RS 72.4
Sara =7+x==72.4+77= RS 79.4
Arslan =3(7+x)=3 x 79.4=RS 238.2
Hey! a+5=7 means that a is the variable, while seven is the answer. My technique is like this: 7-5=2 You need to subtract the numbers you already have. This only works for addition! Hope this helps :) !
The answer is 4+5+6=15.Hope that helps. :)
Answer:
25pi. 36pi
10pi. 12pi
--------------------------
9pi. 49pi
6pi. 14pi