This problem solving activity has an algebra focus.
Mr Morrison and his daughter Rose each get a bottle of QwikQure Cough Medicine from the pharmacy.
Mr Morrison’s bottle has 300ml and he has to take 10ml every 3 hours.
Rose has a smaller bottle with 90ml and she has to take 5ml every 6 hours.
They have to take the medicine between the hours of 7am and 7pm.
Who will use up their medicine first?
To solve this problem, which compares different rates of usage, students should be encouraged to use a graph or a table. Both of these approaches apply and develop the conceptual knowledge that is required to solve more complicated algebraic problems.
The problem is typical of many real world problems such as investment problems, where there are different rates of return, and travel problems where different methods of travel cost different amounts. Therefore, different contexts for the application of this conceptual knowledge could include walking different distances at different speeds and use of other resources (e.g. money).
Mr Morrison and his daughter Rose each get a bottle of QwikQure Cough Medicine from the pharmacy. Mr Morrison’s bottle has 300ml and he has to take 10ml every 3 hours. Rose has a smaller bottle with 90ml and she has to take 5ml every 6 hours. They have to take the medicine between the hours of 7am and 7pm.
Who will use up their medicine first?
Mr Morrison's wife, Mrs Morrison, also has some cough medicine. She must take 10ml every 4 hours. If her bottle lasts as long as her husband’s, how much medicine does her bottle hold.
Use a graph with the horizontal axis marked from 7am to 7pm in hours for about 7 days. Mr Morrison will then use all his medicine up on the sixth day at 7pm. Rose will do the same.
Mrs Morrison will use up 40ml per day (4 doses of 10 ml each). If the bottle lasts six days as her husband’s did, then she will have a bottle of 40 x 6 = 240 ml.
Printed from https://nzmaths.co.nz/resource/qwikqure-medicine at 12:25am on the 29th April 2024