The maker of a fitness and sleep tracking app has found that on average, adults tend to sleep less per night than the recommended amount. The app makers have found that the sleep data follows a normal distribution with a population mean (μ) of 6.9 hours sleep per night and a standard deviation (σ) of 1.2 hours. What is the probability that a randomly selected adult will sleep for:
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", "minValue": "0.75", "maxValue": "0.77", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "2", "showCorrectAnswer": true, "showFeedbackIcon": true, "scripts": {}, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "adaptiveMarkingPenalty": 0, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "prompt": "The recommended amount of sleep is 8 hours. In a sample of 3000 adults, find the expected number of people who are getting more than the recommended amount of sleep per night.
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