2025 AMC 8 Problems/Problem 4: Difference between revisions
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Lucius is counting backward by <math>7</math>s. His first three numbers are <math>100</math>, <math>93</math>, and <math>86</math>. What is his <math>10</math>th number? | |||
==Solution== | |||
By the formula for the <math>n</math>th term of an arithmetic sequence, we get that the answer is <math>a+d(n-1)</math> where <math>a=100, d=-7</math> and <math>n=10</math> which is <math>100 - 7(10 - 1) = \boxed{\text{(B)\ 37}}</math>. | |||
~Soupboy0 | |||
Revision as of 19:24, 29 January 2025
Lucius is counting backward by
s. His first three numbers are
,
, and
. What is his
th number?
Solution
By the formula for the
th term of an arithmetic sequence, we get that the answer is
where
and
which is
.
~Soupboy0