Oliver needed to build 10 chairs to go with a dining room table that he had built. At the start of the second day he had complet
ed 4 chairs, and by the end of second day of work, he had worked for 9 hours and completed 7 chairs in total. How many more hours must he work before he will finish all 10 chairs? A) 3 B) 9 C) 10 D) 18
At the start of 2nd day, he completed 4 chairs....at the end of the day, (9 hrs later) he completed 7 chairs....that means he had completed (7-4) = 3 chairs in 9 hrs. 9/3 = 3...that means it takes 3 hrs to complete 1 chair.
He has 7....so he needs 3 more chairs...and if 1 chair takes 3 hrs, then 3 chairs takes (3 * 3) = 9 hrs <===
That look like an obvious decreasing trend. From the first and last point we get a slope of (9-31)/(92-26) = -1/3 and a y intercept of 31 - (-1/3)26 = 39.67.
