Solution: The element X has three naturally occuring isotopes;  aX, bX, and cX, where a, b, and c represent the mass number. The masses (amu),except aX, and the percent abundances of the isotopes are given in t

The element X has three naturally occuring isotopes;  ^aX, ^bX, and ^cX, where a, b, and c represent the mass number. The masses (amu),except ^aX, and the percent abundances of the isotopes are given in the table below. The average atomic mass of X is 17.20 amu. What is the mass of ^aX in amu?

a. 16.60

b. 16.67

c. 19.01

d. 18.11

e. 9.99