In de rekenkundige rij
7, 11, 15, ..., 143, ...
is 143 één van de termen.
De hoeveelste term is 143 ?
( m.a.w. bepaal n ) 		A.   31
B.   32
C.   33
D.   34
E.   35
A    B    C    D    E 

[ 4-4376 - op net sinds 22.7.2012-(E)-27.10.2023 ]

Translation in   E N G L I S H

7, 11, 15, ..., 143, ...
is an arithmetic sequence.
What is the number (n)
of the term 143 ? 		A.   31
B.   32
C.   33
D.   34
E.   35

Oplossing - Solution

t1 = 7   v = 4
tn = t1 + (n − 1)v
143 = 7 + (n − 1).4
136 = 4(n − 1)
34 = n − 1
n = ...