Round 220 to the nearest 100

If 1 is divided by the sum of y& 4.the result is equal to 3 divided by 4, find the value of m

Determine which postulate or theorem can be used to prove that lmn =nmo

1. according to the internal revenue service, the mean tax refund for the year 2007 was $2,708. assume the standard deviation is $650 and that the amounts refunded follow a normal probability distribution. a. what percent of the refunds are more than $3,000? b. what percent of the refunds are more than $3,000 but less than $4,000? c. what percent of the refunds are less than $2,000?