Earlier quoted context omitted.
Samsung sells a lot of phones but far from the majority of them, they have around 25% of the android market, which means 75% has Chrome installed by default.
Um, I think you misread something - they have ~25% of global smartphone market. They're closer to 50% of Android market.
Android has more than 80% of the smartphone market and Samsung has around 20% of the whole market, which makes 25% of the android market.