The way I read it, you have 8 terms of the first AP, with a = 6400 and d=240
plus 7 terms of a second AP with a = 9500 and d=360
The 15th year would be the 7th term of series #2
term7 = 9500+6(360) = ....
Use your sum of terms formula to find the two sums and add them.
mr mensah starts a job with an annual salary of $6400 which increases by $240 every year after working for eight years mr mensah is promoted to a new post with an annual salary of 9500 which increases by $360 every year calculate mr mensah salary in the fifteenth year of service and mr mensah total earnings at the end of the fifteenth year of service
3 answers
Yes
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