PSLE The first 15 numbers of a number pattern are given.
4, 2, 8, 9, 4, 2, 8, 9, 4, 2, 8, 9, 4, 2, 8, ...
- What is the 285th number?
- What is the sum of the first 156 numbers?
(a)
Each set of numbers: 4, 2, 8, 9
Each set has 4 numbers.
Remainder: 1 → Number 4
Remainder: 2 → Number 2
Remainder: 3 → Number 8
Remainder: 0 → Number 9
285 ÷ 4 = 71 r 1
285th number = 4
(b)
Sum of each set
= 4 + 2 + 8 + 9
= 23
Number of sets
= 156 ÷ 4
= 39 r 0
Sum of the first 156 numbers
= 39 x 23
= 897
Answer(s): (a) 4; (b) 897