Final answer:
To add the given numbers, convert them to decimals and add them together to get the sum to the nearest hundredth.
Step-by-step explanation:
To add the given numbers in decimal form, we need to convert them first. -1 1/4 can be written as -1.25, 0.75 remains the same, and 0.45 remains the same. Now we can simply add these decimals: -1.25 + 0.75 + 0.45 = 0.95. Therefore, the sum as a decimal to the nearest hundredth is 0.95.
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