Soong Rui Kai's answer to Anugerah's Primary 6 Maths Data Analysis Singapore question.
done
{{ upvoteCount }} Upvotes
clear
{{ downvoteCount * -1 }} Downvotes
Lowest Common Multiple of 2,3,5 is 30.
All 3 lights will blink together every 30minutes.
First time they blink together is 7pm.
They will blink together again at 7.30pm, 8pm, 8.30pm, 9pm, 9.30pm, 10pm, 10.30pm, 11pm.
The question asks how many times they will blink together between 7.15pm and 10.50pm.
By counting we see that the answer is 7
All 3 lights will blink together every 30minutes.
First time they blink together is 7pm.
They will blink together again at 7.30pm, 8pm, 8.30pm, 9pm, 9.30pm, 10pm, 10.30pm, 11pm.
The question asks how many times they will blink together between 7.15pm and 10.50pm.
By counting we see that the answer is 7
Date Posted:
4 years ago
360 Tutoring Program