CY Lew's answer to Sandy's Primary 6 Maths Speed Singapore question.

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CY Lew
Cy Lew's answer
89 answers (A Helpful Person)
1st
a) At the 1st meeting, using speed triangle,
90xT + 110xT = 400
T = 2 min
Distance covered by Allen = 90x2=180 m

b) Time for each lap,
Aileen = 400 ÷ 90 = 40/9 min
Betty = 400 ÷ 110 = 40/11 min
Using HCF n LCM,
Next meeting occurs at the end of,
Betty's 11th lap n Aileen's 9 lap
Thus,
Time = 40 min later
Sandy
Sandy
2 years ago
Thank you so much for your valuable time