PSLE The first 15 numbers of a number pattern are given.
1, 0, 5, 4, 1, 0, 5, 4, 1, 0, 5, 4, 1, 0, 5, ...
- What is the 678th number?
- What is the sum of the first 251 numbers?
(a)
Each set of numbers: 1, 0, 5, 4
Each set has 4 numbers.
Remainder: 1 → Number 1
Remainder: 2 → Number 0
Remainder: 3 → Number 5
Remainder: 0 → Number 4
678 ÷ 4 = 169 r 2
678th number = 0
(b)
Sum of each set
= 1 + 0 + 5 + 4
= 10
Number of sets
= 251 ÷ 4
= 62 r 3
Sum of the first 3 numbers
= 1 + 0 + 5
= 6
Sum of the first 251 numbers
= (62 x 10) + 6
= 620 + 6
= 626
Answer(s): (a) 0; (b) 626