1. "Remember that puzzle I solved?" asked Ken. "About a phone number?" Tony replied, "There was the old 4-digit part, and the new 3-digit exchange bit." "That's right," Ken told him. "Well, now I've made one up on our own number. If you square our 4-digit part you get exactly seven times our complete 7-digit number." This may well challenge you, but what was their number?

273 - 4375

390-8372

284-2993