The sales tax rate is 8.5%. what is the total cost, including tax, of an item priced at $40.50

133 ≤ x ≤ 148

We first take Corey's weight off of the total:

405-127 = 278

The other two boys together weigh 278.

We know that Alex weighs no more than 145 and no less than 130. Taking these two numbers off of the 278 will give us the constraints for Carl's weight:

278-145 = 133

278-130 = 148

This means that 133 ≤ x ≤ 148