Answer: There are 25 red flowers in Sakura's garden.
Step-by-step explanation: Given that in Sakura's garden, for every 5 red flowers there are 10 yellow flowers and there are a total of 75 yellow and red flowers in her garden.
We are to find the number of red flowers in Sakura's garden.
Let the number of red flowers and yellow flowers in Sakura's garden be 5x and 10x respectively.
Then, according to the given information, we have

Therefore, the number of red flowers is given by

Thus, there are 25 red flowers in Sakura's garden.