Help on a stats homework question!?

According to a recent census, 75% of all households in the United States were composed of only one or two persons. uming this percentage is still valid today, what is the probability that between 6630 and 665, inclusive, of the next 1000 randomly selected households in America will consist of either one or two persons? (Use the normal approximation to the binomial and show your work. Check the np and nq condition to be sure it is appropriate to use the normal approximation to the binomial)