J's answer to Happy's Primary 5 Maths Rate & Ratio Singapore question.
done
{{ upvoteCount }} Upvotes
clear
{{ downvoteCount * -1 }} Downvotes
Number of adults who left the park = 160 - 68 = 92
⬛ represents 1 unit of adults
⬜ represents 1 unit of children
From the ratios, we can say that :
Children who left : ⬜⬜
Children remained : ⬜⬜⬜
Adults who left : ⬛⬛
Adults remained : ⬛
Based on the ratios and numbers,
⬛⬛⬜⬜ = 92 ①
⬛⬜⬜⬜ = 68 ②
Notice that these two models have everything the same except 1 ⬜ and 1⬛
So the difference between ⬛ and ⬜ = 92 - 68 = 24
So ⬛ is 24 more than ⬜
We can now rewrite ② as :
⬜ + 24 + ⬜⬜⬜ = 68
⬜⬜⬜⬜ = 68 - 24
⬜⬜⬜⬜ = 44
⬜ = 44 ÷ 4 = 11
Children who were at the park in the morning = ⬜⬜⬜⬜⬜ = 11 x 5 = 55
⬛ represents 1 unit of adults
⬜ represents 1 unit of children
From the ratios, we can say that :
Children who left : ⬜⬜
Children remained : ⬜⬜⬜
Adults who left : ⬛⬛
Adults remained : ⬛
Based on the ratios and numbers,
⬛⬛⬜⬜ = 92 ①
⬛⬜⬜⬜ = 68 ②
Notice that these two models have everything the same except 1 ⬜ and 1⬛
So the difference between ⬛ and ⬜ = 92 - 68 = 24
So ⬛ is 24 more than ⬜
We can now rewrite ② as :
⬜ + 24 + ⬜⬜⬜ = 68
⬜⬜⬜⬜ = 68 - 24
⬜⬜⬜⬜ = 44
⬜ = 44 ÷ 4 = 11
Children who were at the park in the morning = ⬜⬜⬜⬜⬜ = 11 x 5 = 55
Date Posted:
3 years ago
Thank you!
Welcome. There's a typo in the first line. It should be 'number of adults and children who left the park' instead
360 Tutoring Program