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Sir can u please suggest me how to solve 13 problem
Answers (5)
There are 2 methods Given: b( birth rate)=39.4/1000, d(death rate)= 19.4/1000 b-d= 39.4-19.4=20/1000 (i.e.0.02=2%) P( population) = 2P( population) To find: n=? Solution :Let's assume P=1000 applying formula: An= p(1+i)^n Putting values: 2000=1000(1+0.02)^n 2=1.02^n n=35 years. Alternative(short method) : the Rule of 70 which is a simple way to calculate the approximate number of years it takes for the level of a variable growing at a constant rate to double. This rule states that the approximate number of years n for a variable growing at the constant growth rate of R percent, to double is n = 70/R Since B-D = 39.4-19.4 = 20 normalized to 1000 = 2% The n = 70/2 = 35
Thread Starter
sai tIs rule 70 is applicable to ca foundation level
You can always use rule of 69,70 or 71 to approximate the answer.
CA Suraj Lakhotia Admin
You can always use rule of 69,70 or 71 to approximate the answer.
where this rule available sir is this was taught in videos sir
Thread Starter
sai tIs rule 70 is applicable to ca foundation level
Basically its is "rule of 72" is simple way to determine how long will ur investment 'double' given in fixed annual rate..but i used 70 in this sum for just convenience thats it. Remember if something increase in fixed annual rate(R) and u required to find a time(N) in certain interest to take the value double. U can use "rule of 72" for to get aprox answer N=72/R