Question

i bought a vegetable seed pocket containing 20 seeds. A manufacturer label on the pocket said that the seeds have at least 90% germination rate. I planted all 20 seeds following their instructions in preparing soil and water. They told me if an "unlikely event" happens, return the packet. Any event which is less than 5% chance of happening is considered an unlikely event. Should i consider less than or equal to 17 germinating an "unlikely event"? The answer is no. Why?