MathsFormula
Junior Member
- Joined
- Jul 13, 2014
- Messages
- 94
The question is:
The total mass of a jar one-quarter full of jam is 250g. The total mass of the same jar three-quarter full of jam is 350g. What is the mass of the empty jar? The answer is 200g
I think I’ve gone about the question the wrong way. I think it’s meant to be a simple arithmetic sum but I’ve made it into basic algebra.
J = JAM X = WEIGHT OF JAR
So (3/4)J +X = 350 .......... (1/4)J +X = 250
X = 350-(3/4)J ................. X = 250-(1/4)J
Using simultaneous equations J = 200
Now putting J = 200 into the formula X = 250-(1/4)J gives X = 200g (the weight of the empty jar).
Someone did actually show me a basic arithmetic way of doing the sum and it took them 2 minutes from first glance at the question. I just nodded my head in agreement but I didn’t know what they were talking about. Please advise. Thanks.
[Can someone show me how to post proper formula symbols on here like the ones they post on the algebra threads. Thanks]
The total mass of a jar one-quarter full of jam is 250g. The total mass of the same jar three-quarter full of jam is 350g. What is the mass of the empty jar? The answer is 200g
I think I’ve gone about the question the wrong way. I think it’s meant to be a simple arithmetic sum but I’ve made it into basic algebra.
J = JAM X = WEIGHT OF JAR
So (3/4)J +X = 350 .......... (1/4)J +X = 250
X = 350-(3/4)J ................. X = 250-(1/4)J
Using simultaneous equations J = 200
Now putting J = 200 into the formula X = 250-(1/4)J gives X = 200g (the weight of the empty jar).
Someone did actually show me a basic arithmetic way of doing the sum and it took them 2 minutes from first glance at the question. I just nodded my head in agreement but I didn’t know what they were talking about. Please advise. Thanks.
[Can someone show me how to post proper formula symbols on here like the ones they post on the algebra threads. Thanks]
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