Let X be the number of miles he rode the first day then
X+(X-6)+(x-6-6)+(x-6-6-6)+(x-6-6-6-6)=120
The rest is up to you!
need help
word problem
darren went on holiday.in 5 days he rides his bike 120 miles.each day he rode 6 miles less than the previous day .how many miles did he ride each day ?.if he went on riding his bike 6 miles less each day,how far would he have ride altogether?
You would get an arithmetic sequence with common difference -6 and first term 120.
5th day:
In your case n=5, d=-6, a= 120.
You can use the recurrent relation for the days in between:
with the terms same as above.
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For the total use the formula for the sum of an arithmetic sequence:
with the terms the same as above