Help! I don’t get it neks

Asilkworm winds its cocoon out of one long silk fiber. to make silk thread, 3 to 10 of these silk fibers are unwound from their cocoons and combined into aa single thread with a typical length of 300 yards. choose a reasonable number of silk fibers in a thread write an equation to find the total length of the silk fibersused in 300 yards of the thread

Lisa has three classes that each last 50 minutes. what is the total number of minutes of the three classes

Ineed i been stuck on this question since yesterday