PSLE The first 15 numbers of a number pattern are given.
3, 5, 4, 6, 3, 5, 4, 6, 3, 5, 4, 6, 3, 5, 4, ...
- What is the 143rd number?
- What is the sum of the first 341 numbers?
(a)
Each set of numbers: 3, 5, 4, 6
Each set has 4 numbers.
Remainder: 1 → Number 3
Remainder: 2 → Number 5
Remainder: 3 → Number 4
Remainder: 0 → Number 6
143 ÷ 4 = 35 r 3
143rd number = 4
(b)
Sum of each set
= 3 + 5 + 4 + 6
= 18
Number of sets
= 341 ÷ 4
= 85 r 1
First 1 number = 3
Sum of the first 341 numbers
= (85 x 18) + 3
= 1530 + 3
= 1533
Answer(s): (a) 4; (b) 1533