Ask Singapore Homework?

Upload a photo of a Singapore homework and someone will email you the solution for free.



Question

Secondary 1 | Maths
2 Answers Below

Anyone can contribute an answer, even non-tutors.

Answer This Question
Alaya
Alaya

Secondary 1 chevron_right Maths chevron_right Singapore

Pwease help me

Date Posted: 3 years ago
Views: 455

See 2 Answers

done {{ upvoteCount }} Upvotes
clear {{ downvoteCount * -1 }} Downvotes
Wan Muhammad Haris Murshidi
Wan Muhammad Haris Murshidi's answer
2 answers (Tutor Details)
1st
Hi!

(a) To find highest common factor (HCF), you want to multiply the prime factors which are common to the numbers.

180 = 2^2 × 3^2 × 5
784 = 2^4 × 7^2

The largest factors shared by both numbers is 2^2.(since 180 cannot be divided by 7, and 784 cannot be divided by 3 or 5)

So the HCF is 2^2 = 4.


(b) Given the expressions of 180 and 784 as prime factors (shown above), we may express 180x784 as...

180 × 784 = 2^6 × 3^2 × 5 × 7^2

In order for 180×784×m to be cube-rootable, all their prime factors need to be in powers of 3 (or multiples of 3).

So 180 × 784 × m would be 2^6 × 3^3 × 5^3 × 7^3,
m = 3 × 5^2 × 7 = 525


(c)
180 = 2^2 × 3^2 × 5
16 = 2^4

Lowest common multiple (LCM) = 2^4 × 3^2 × 5
= 720

Hence,
180n = 720
n = 4

Hope this helps!
done {{ upvoteCount }} Upvotes
clear {{ downvoteCount * -1 }} Downvotes
Matthew Soon
Matthew Soon's answer
94 answers (Tutor Details)
Alaya
Alaya
3 years ago
Thank uuuu