Tiêu đề MSTE 1 Solutions.pdf ✅

▣ 4. On the first six tests in her Math subject, her scores were 92, 78, 86, 92, 95, and 91. If she took the seventh test and raised the mean of her scores exactly one point, what was here score on the 7th test? [SOLUTION] Let x be the score on the 7 th test. 92 + 78 + 86 + 92 + 95 + 91 6 + 1 = 92 + 78 + 86 + 92 + 95 + 91 + x 7 x = 96 ▣ 5. Earth is approximately 93 000 000 miles from the sun. Jupiter is approximately 484 000 000 miles away from the sun. How long would it take a spaceship traveling at 7 500 mph to fly from Earth to Jupiter? [SOLUTION] The distance from Jupiter to Earth is 484 000 000 − 93 000 000 = 391 000 000 miles 391 000 000 mi 7500 mi/hr × 1 day 24 hr × 1 year 365 days = 5.95 years ▣ 6. Divide 253 into 4 parts proportional to 2, 5, 7, 9. What is the value of the largest part? [SOLUTION] Since the proportion is 2: 5: 7: 9, then the parts are in the form 2k, 5k, 7k, 9k where k is a real number. 2k + 5k + 7k + 9k = 253 k = 11 Therefore, the largest part is 9k = 9(11) = 99 . ▣ 7. On a Richter scale, the magnitude R of an earthquake of intensity I is given by R = log I I0 where I0 is a certain minimum intensity. If the intensity of an earthquake is 1000I0, find R. [SOLUTION] Substitute I = 1000I0, R = log 1000I0 I0 R = 3