Question: Tommy wanted to buy a gold ring which costs $121 by saving money. His first day savings are $6 . Each succeeding day he saves $1 more than the previous day. With this pattern of savings, in how many days can he buy the ring? Steps to derive 1 The money Tommy saves increases by $1 each day. So, daily savings form an arithmetic sequence: 6, 7, 8, 9, .....2 Let $121 will be the sum to n 3 S n n [ 2 a 1 + ( n - 1 ) d ] 2 4 121 = n [ 2 ( 6 ) + ( n - 1 ) 1 ] 2 S n a 1 d 5 242 = n n 6 242 = n 2 n 7 n 2 n 8 n n 9 So, Tommy can buy the ring in 11 days.n Hence the right answer is Option A Click Here To Go Back What is the distance from the vertex to the focus of the parabola y = 0.5x2?.. What is the standard form of a parabola with vertex (2, 4) and focus (2, 8)?.. Find the equation of the parabola in the standard form opens to the left with (- 1, - 5) a.. Find the distance from the focus to the directrix of a parabola x2 = 16y... 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