Answer:
0.15 expressed as a fraction in its simplest form is 3/20.
Explanation:
To express a terminating decimal as a fraction:
Step 1
Write the decimal as a fraction by dividing it by 1:

Step 2
Multiply the numerator and denominator by 10 for every number after the decimal point.
As there are two numbers after the decimal point, multiply the numerator and denominator by 100:

Step 3
Find the highest common factor (HCF) of the numerator and denominator.
- Factors of 15: 1, 3, 5 and 15.
- Factors of 100: 1, 2, 4, 5, 10, 20, 25, 50 and 100.
Therefore, the HCF of 15 and 100 is 5.
Divide the numerator and denominator by the HCF to reduce the fraction to its simplest form:

Conclusion
0.15 expressed as a fraction in its simplest form is 3/20.