Final answer:
To add the given complex numbers, separate and combine the real parts and the imaginary parts, respectively, resulting in the complex number 6.8 - 9.1i.
Step-by-step explanation:
The question requires us to combine complex numbers and express the result in the standard form a + bi, where a is the real part and b is the imaginary part of the complex number. To do this, we combine like terms, adding the real parts and the imaginary parts separately.
The real parts are: 9.3 (from the first number) + 6.2 (from the second number) - 8.7 (from the third number). Meanwhile, the imaginary parts are: -0.1i (from the first number) - 1.4i (from the second number) - 7.6i (from the third number).
Adding the real parts: 9.3 + 6.2 - 8.7 = 6.8
Adding the imaginary parts: -0.1i - 1.4i - 7.6i = -9.1i
Therefore, the result in the form a + bi is 6.8 - 9.1i.