Let B(t) be the number of Bieber followers on Twitter and let P(t) be the number of Perry followers on Twitter, where t is the number of days after March 1st, 2016. According to TwitterCounter: Date Bieber Followers (bieberliebers) Perry Followers (Katycats) 1st March 2016 76401405 83707468 1st May 2016 80714571 87910848 The logistic curve is used to model population growth, such as worldwide population or the spread of infectious diseases such as bieberfever. The logistic curve has equation: a(1+tanh(bt+c)). Where t is measured as the number of days after March 1st, 2016 and a, b and c are constants determined by the data. The number of Bieber followers on Twitter (in millions) is approximately: B(t) = 44(1+tanh(0.0048t + 0.955)). Similarly, the number of Perry followers on Twitter (in millions) is approximately: Since P(t)=53(1+tanh(0.0019t+0.644)). lim a(1+tanh(bt+c)) : t = we can project that the number of Twitter followers for Bieber and Perry will approach the following quantitites: lim B(t) = t lim P(t)= t