Customers of brands AW, TG and YM are generally loyal to their product brands. However, through clever marketing and adv

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Customers of brands AW, TG and YM are generally loyal to their
product brands. However, through clever marketing and advertising,
they may be persuaded to switch brands. Customer loyalty to a given
brand is estimated at 75%. Hence, the competitors have only a 25%
chance of realising a switch. Competitors launch their advertising
campaigns once a year. For AW customers, the probabilities of
switching to brands TG and YM are 0.1 and 0.15 respectively.
Customers of brand TG are likely to switch to AW and YM with
probabilities 0.2 and 0.05. Brand YM customers can switch to brands
AW and TG with equal probabilities
On average, how long will brand YM customers take to
switch back to brand YM for the first time?