TIFR 2020

Question

As of May 3, 2020 number of COVID-19 cases in India are 1.1 % of total worldwide reported cases. Out of which, 3 % have been reported in death and 27 % recovered. In the remaining active cases, only 4.5 % are critical. If the number of critical cases is 1400, the total number of worldwide COVID-19 cases on May 3, 2020 are

(A) 32 lakhs

(B) 28.3 lakhs

(C) 40 lakhs

(D) 31.1 lakhs

Answer 1

Answer: Option (C)

Let the total number of worldwide COVID-19 cases = $x$

Now 1.1% of $x$ are the number of cases in India i.e. 

Cases in India = $0.011*x$

Total active cases in India = $(1-0.03-0.27)*0.011x$ = $0.0077x$

Out of which only $4.5$% are critical i.e.

Total critical cases in India = $0.045*0.0077x$ = $0.0003465x$

We have given number of critical cases = $1400$

$0.0003465x$ = $1400$

$x$ = $\frac{1400}{0.0003465}$ ≈ $40Lakhs$