Respuesta :

10.5, 11, 11.5, 12, 12.5...this is an arithmetic sequence with a common difference of 0.5

an = a1 + (n - 1) * d
n = term to find = 23
a1 = first term = 10.5
d = common difference = 0.5

sub and solve

a(23) = 10.5 + (23 - 1) * 0.5
a(23) = 10.5 + 22 * 0.5
a(23) = 10.5 + 11
a(23) = 21.5 <===