The working shown in the photo is incorrect. Get the student to draw a model to represent the problem and he/she will have a better idea what to do with the numbers. Questions to start off: (1) who is the shortest among the three people? Can I draw a bar to represent the shortest person? (2) what would the bars for the other two people look like? Can I draw the bars and put the information onto the diagram? (3) what other info is given that I can include on the diagram? (4) after the model is drawn, start thinking of what numbers to add, subtract, etc to solve.

Got it. Thx

Difference between amount of sugar owned by boys does not change.

Sorry. I do not understand

Since both boys used equal amount of sugar, the difference in the mass of sugar does not change

Still no idea

Whats the difference between the mass of sugar owned by the two boys?

1200g

Since the two boys used equal amounts of sugar, what is the difference in the mass of sugar in the end?

2500g?

Equal amount of sugar is used by both boys. If Raymond uses 1g, than Darren will also use 1g. If Raymond uses 100g, then Darren will also use 100g.

Sorry...still cannot catch

Try drawing out a model

Okay

Here's the model to help... In the question, since both used the same amount of sugar, it is easier to 'take away' that amount from both bars from the left hand side of the bars so that we can compare and make the 'twice as much' more visible. Hope you can continue from here to solve....? To check whether your answer is correct, put it back into the problem and work backwards and see if it satisfies the conditions in the problem.

I swear I didn't buy 2500g of sugar... lol

Lol raymond 😂😂😂

Tip: difference of water between both jugs does not change

Got it. Thx

Here's the visual representation of the problem. Similar to the other problem -- since an equal amount was removed from each jug, we can 'take away' from the left hand side of the bars in order to compare and make it easier to see the '8 times as much'.