Stage 2-Brainwave 10


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Brainwave 10

Heavy Pets

Scales
Briony wanted to know the weight of her pets but they wouldn't stay on the scales. To solve the problem she stood on the scales and held the pets.
Firstly she stood on the scales with her cat and wombat and the total mass was 85kg.
Next she stood on the scales with her dog and wombat and the scales read 87kg.
Finally she stood on the scales with her cat and dog and the total was 82kg.
Briony knew she weighed 60kg.
How much did each pet weigh?

Feature Solution

The feature solution for the problem came from Jack, Tiah, Joab & Darcy from Blighty PS

What did you have to find out?
We had to find out what each pet weighed individually.

What materials did you use?
We used pencil, paper and the Smartboard.

How did you think? What strategies did you use? How did you solve this problem?
We drew a picture, acted it out, looked for a pattern.We also worked backwards and we used a number sentence.

We didn't use the investigation sheet.

What answers did you come up with?
Briony = 60kg

Cat + Wombat = 25kg

Dog + Wombat = 27kg

Cat + Dog = 22kg

The difference between the Cat + Wombat and Dog + Wombat is 2 kg. Therefore the dog weighs 2kg more than the cat.

So we took 2 off 22 and then halved it which means the cat weighs 10kg and the dog weighs 12kg.

10kg + Wombat = 25kg

Therefore the Wombat weighs 15kg.

We checked it by working out Dog + Wombat.

12kg + 15 kg = 27kg. This is correct.

Briony 60kg

Dog 12kg

Cat 10kg

Wombat 15kg

Commendable contributors to the problem were:
Mahalia & Jessica; Marni & Libby from Moama PS
Year 3 from St Josephs Blayney
Georgia & Melissa; Jack & Wayne; Sam & Jamin from Stockinbingal PS
Abbey, Emma P, Emma C, Jorja, Sian, Taylah & Sybila from Barham PS
Jacob; Lachlan from Kempsey East PS
Tom, Maddie, Taya & Zac from Bellingen PS
Jack, Liam & Hayley; Dru, Andy & Jack; Grayson, Dylan & Steven; Gemma & Yoona; Angela, Vivien, Parvathi & Apoorva; Emily, Ashleigh & Hayley; Bridget & Jacob from Kaleen Primary School

Solutions were also sent in by:
Oliver from Bello PS
Joe & Josh; Tommy; Peter; Jack; Daisy & Chelsea; Sadie & Chloe; Clancy from Tottenham CS
Joshua & Alex from St Brigids
Jacob; Jakala; Courtney; Kyle & Jackson from Spencer PS