New PMP Question & Answers with explanation

Your selection committee can choose only one of the following projects: Project A’s original investment is $1 million, and the payback period is 18 months. Project B’s original investment is $1.4 million, and the payback period is 18 months. Project C’s original investment is $1.8 million, and the payback period is 18 months. Which project should the committee choose?
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The project management team is coordinating the decision between making or buying a product. Making the product would require an initial investment of $35,000 and has a probability of 15 percent failure and a probable impact of $15,000. Buying the product would require an initial investment of $25,000 but has a probability of 35 percent failure and $10,000 impact. What is the expected monetary value of making the product?
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You have selected a vendor and are meeting with them to begin discussing the details of the final contract. They tell you that the equipment originally bid in the RFP is no longer available. They say the best solution is to buy the new equipment they’re offering, which costs more than the original equipment. You have concerns that the new equipment might not be compatible with existing equipment and discuss this with them. After further investigation, it’s proven the new equipment will work, and the vendor agrees to add some additional training time to help offset the difference in price. Which of the following tools and techniques of the Conduct Procurement process does this describe?
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A project team is using iterations within the project to introduce new functionality and complete the project deliverables. What development life cycle is the project team following?
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Using a triangular distribution formula, calculate the cost estimate based on the following three-point estimates: Optimistic = $2,500, Most Likely = $3,500, Pessimistic = $7,200.
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