Calculate the following decimal operations and round to two decimal places where indicated.

$$7.123 + 12.567 = 19.690$$

The answer is $\boxed{19.69}$

b)

$$65.34 - 1.286 = 64.054$$

The answer is $\boxed{64.054}$

c)

$$987.543 - 32.431 = 955.112$$

The answer is $\boxed{955.112}$

3. Calculate the following and then round off your answer to two decimal places:

a)

The third decimal digit is 5, so round up the second decimal digit.

$$42.5359 \approx 42.54$$

The answer is $\boxed{42.54}$

b)

$$98.4311 - 88.31 + 54.1034$$ $$10.1211 + 54.1034 = 64.2245$$

The third decimal digit is 4, so keep the second decimal digit as is.

$$64.2245 \approx 64.22$$

The answer is $\boxed{64.22}$

c)

$$0.45 - 0.003 - 0.001$$ $$0.447 - 0.001 = 0.446$$

The third decimal digit is 6, so round up the second decimal digit.

$$0.446 \approx 0.45$$

The answer is $\boxed{0.45}$