People often add fruit to yogurt, and eat the yogurt mixed with the fruit. Generally, there is more yogurt than fruit, such that the yogurt constitutes the primary component of the mixture. As such, one would recite "She’ha’kol" over the yogurt, and this Beracha covers also the fruit. If a person adds so much fruit that the fruit now constitutes the majority, then he recites "Ha’etz," and this Beracha covers both the fruit and the yogurt.
A more complicated question arises in the common case where pieces of granola are added to the yogurt. This question is complicated because the Beracha recited over granola depends on how the granola was produced by the company. Some companies produce granola by dry roasting oats (as do most Israeli companies which produce granola), in which case the proper Beracha is "Ha’adama." Although oats are among the five grains over which one recites "Mezonot," the Beracha of "Mezonot" is required only if the grain was ground into flour and baked, or if the grain was boiled in water. If it was merely dry roasted, then the Beracha remains "Ha’adama." As different companies produce granola through different methods, it is important to determine the method used in the production of the granola one consumes in order to determine the proper Beracha.
With this in mind, let us return to the question of yogurt mixed with granola. If the granola is of the type which requires "Mezonot," as the oats were cooked in water, then we apply the general rule that a "Mezonot" food is always regarded as the primary component of a mixture. Therefore, one would recite "Mezonot" over the yogurt and granola, and both would be covered, even if there is more yogurt than granola. If, however, the granola is of the type that requires "Ha’adama," as the oats were dry roasted, then the Beracha is determined by the majority of the mixture. If there is more yogurt than granola, then one would recite "She’ha’kol," whereas if there is more granola than yogurt, then the Beracha is "Ha’adama."
Summary: If one puts fruit into yogurt and mixes them together, then he recites "She’ha’kol" over the entire mixture, unless there is more fruit than yogurt, in which case he recites "Ha’etz" over the entire mixture. If one eats yogurt with granola, then if the granola is of the kind that requires "Mezonot" (meaning, the oats were boiled in water), then he recites "Mezonot" over the entire mixture regardless of the amount of granola it contains. If the granola is of the kind that requires "Ha’adama" (meaning, the oats were dry roasted), then one recites "She’ha’kol," unless the granola constitutes the majority, in which case one recites "Ha’adama." In general, when eating granola, one must determine the process by which it was produced in order to know which Beracha to recite.