The flow rate of a coolant into a chemical reactor, RtR_tRt, is adjusted every minute such that the sequence of flow rates forms an arithmetic progression, where t t\,t is the time in minutes.
In the 4th minute, the flow rate is 40 L/min. The total volume of coolant delivered during the first 10 minutes is 325 L. Determine the initial flow rate, aaa, and the constant change in flow rate per minute, ddd.
A secondary auxiliary system has an initial flow rate of 6 L/min, which increases by 2 L/min each minute. The total volume delivered by this auxiliary system over n n\,n minutes is TnT_nTn. Find the value of n n\,n such that the total volume delivered by the primary system, SnS_nSn, is equal to TnT_nTn, where n>0n > 0n>0.
308 exam-style questions on OCR (MEI) A Level Maths 1.6 Sequences and Series, covering 1.6.1 Binomial expansion for positive integer n, 1.6.2 Factorial and combinations notation, 1.6.3 Binomial expansion for rational n (A-level only), 1.6.4 Binomial expansion of (a + bx)^n via factoring (A-level only), 1.6.5 Binomial approximating polynomials (A-level only), 1.6.6 What a sequence is; finite and infinite (A-level only), 1.6.7 Generate a sequence by formula or recurrence (A-level only), 1.6.8 A series as a sum of terms (A-level only), 1.6.9 Sigma notation (A-level only), 1.6.10 Increasing, decreasing and periodic sequences (A-level only), 1.6.11 Convergent and divergent sequences (A-level only), 1.6.12 Arithmetic sequences and series (A-level only), 1.6.13 Standard formulae for arithmetic series (A-level only), 1.6.14 Geometric sequences and series (A-level only), 1.6.15 Standard formulae for geometric series (A-level only), 1.6.16 Sum to infinity of a geometric series (A-level only), and 1.6.17 Sequences and series in modelling (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.