7 times a number increased by 4?

To express "7 times a number increased by 4" mathematically, you would write it as 7x + 4, where x represents the unknown number. This expression indicates that you multiply the number by 7 and then add 4 to the result. So, if the number is 5, the expression would be 7(5) + 4 = 35 + 4 = 39.