Help me please i need you to choose the correct fractions

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

Which of these people has balanced their checkbook correctly? oa. gary: the balance in his check register is $500 and the balance in his bank statement is $500. b. gail: the balance in her check register is $400 and the balance in her bank statement is $500. c. gavin: the balance in his check register is $500 and the balance in his bank statement is $510.

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.