Financial Questions help (1 Viewer)

kpad5991

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1) Sally makes a cordial drink so that 10% of the drink is cordial concentration.. The rest is water. Sally has 350ml of the drink in a jug. She decided that she wants the concentrate to be only 8% of the drink. How much extra water does she need to add to the jug?

2) A diary farmer found that the milk supplied by his cows was 5% cream and 95% skimmed milk. How much skimmed milk he should add to a litre of milk to reduce the percentage of cream to 4%?

3) The cost of a car is reduced by 5% and then that price is then increased by 10%. The car now sells for $28 000. What was the original price of the car?

4) Natural fruit juice contains 80% water. In concentrating the juice, 75% of the water is removed. What is the percentage of water in the concentrated juice?

5) The yearly changes in population in a town for four consecutive years were, respectively 20% increase, 20% decrease, 20% increase, 20% decrease. What is the net percentage change over the four years to the nearest percent?
 

5uckerberg

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1) Sally makes a cordial drink so that 10% of the drink is cordial concentration.. The rest is water. Sally has 350ml of the drink in a jug. She decided that she wants the concentrate to be only 8% of the drink. How much extra water does she need to add to the jug?

2) A diary farmer found that the milk supplied by his cows was 5% cream and 95% skimmed milk. How much skimmed milk he should add to a litre of milk to reduce the percentage of cream to 4%?

3) The cost of a car is reduced by 5% and then that price is then increased by 10%. The car now sells for $28 000. What was the original price of the car?

4) Natural fruit juice contains 80% water. In concentrating the juice, 75% of the water is removed. What is the percentage of water in the concentrated juice?

5) The yearly changes in population in a town for four consecutive years were, respectively 20% increase, 20% decrease, 20% increase, 20% decrease. What is the net percentage change over the four years to the nearest percent?
1. Here are my hints. 10% of the drink is cordial and that you have 350mL of the drink at the start. First question what is 10% of 350mL, or you can go if 100 stands for 350 then what is 10 using the fact that percent is per a hundred. Then if we want that to be 8% only how much water do we need so that instead of being 10% it is only 8%?

2. We have one litre of milk here and from the composition we need to find what is 5% of one litre which is cream because our emphasis is on the cream. Now the next part of the question is that how much skimmed milk is needed so that the 5% of one litre is 4% ask yourself in the new sample what is a quarter of the cream amount and multiply by 100.

3. Start this question you need to see what this question is asking us to do. Now time to get into it. the cost of a car is reduced by 5% and then increased by 10% what is this telling us. Well if we reduce something by 5% we have 95% leftover and then if you increase something by 10% it is simply just 95% + 9.5% = 104.5%. One can also express this idea using fractions.

4. The easiest one to complete because you simply have to do these steps, start off with the fact that 80% of the water can be treated as a whole, now my question is what is one quarter of 80%. Once this step is answered ask yourself what is three quarters of that which can simply be done by multiplying by 3. Last step 80% - (...) = Percentage of water in the concentrated juice.

5. This is an interesting take because there is actually a very clever way that we can do this question. You see here that you have a 20% increase and then a 20% decrease right. Well guess what it happens twice so the way how I would approach such a question is to use decimals because they provide that info very clearly. Well you see

Find that and then numtiply by 100 to convert from decimals to percentages and then round it to the nearest percent and then the question is done.
Please note decimal comes from deci which is simply divided by 10 and then percent is simply per 100 as in per + century.
 

kpad5991

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1. Here are my hints. 10% of the drink is cordial and that you have 350mL of the drink at the start. First question what is 10% of 350mL, or you can go if 100 stands for 350 then what is 10 using the fact that percent is per a hundred. Then if we want that to be 8% only how much water do we need so that instead of being 10% it is only 8%?

2. We have one litre of milk here and from the composition we need to find what is 5% of one litre which is cream because our emphasis is on the cream. Now the next part of the question is that how much skimmed milk is needed so that the 5% of one litre is 4% ask yourself in the new sample what is a quarter of the cream amount and multiply by 100.

3. Start this question you need to see what this question is asking us to do. Now time to get into it. the cost of a car is reduced by 5% and then increased by 10% what is this telling us. Well if we reduce something by 5% we have 95% leftover and then if you increase something by 10% it is simply just 95% + 9.5% = 104.5%. One can also express this idea using fractions.

4. The easiest one to complete because you simply have to do these steps, start off with the fact that 80% of the water can be treated as a whole, now my question is what is one quarter of 80%. Once this step is answered ask yourself what is three quarters of that which can simply be done by multiplying by 3. Last step 80% - (...) = Percentage of water in the concentrated juice.

5. This is an interesting take because there is actually a very clever way that we can do this question. You see here that you have a 20% increase and then a 20% decrease right. Well guess what it happens twice so the way how I would approach such a question is to use decimals because they provide that info very clearly. Well you see

Find that and then numtiply by 100 to convert from decimals to percentages and then round it to the nearest percent and then the question is done.
Please note decimal comes from deci which is simply divided by 10 and then percent is simply per 100 as in per + century.
For question 4 the answer is 50% using your hints does not give me 50% and I still do not get Q2 and Q1 and Q4 (50% as the answer) Please help
 

kpad5991

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For question 4 the answer is 50% using your hints does not give me 50% and I still do not get Q2 and Q1 and Q4 (50% as the answer) Please help
Also Q3 the answer is $26 790 using your hints I got $26 923.08
 

5uckerberg

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1) Sally makes a cordial drink so that 10% of the drink is cordial concentration.. The rest is water. Sally has 350ml of the drink in a jug. She decided that she wants the concentrate to be only 8% of the drink. How much extra water does she need to add to the jug?

2) A diary farmer found that the milk supplied by his cows was 5% cream and 95% skimmed milk. How much skimmed milk he should add to a litre of milk to reduce the percentage of cream to 4%?

3) The cost of a car is reduced by 5% and then that price is then increased by 10%. The car now sells for $28 000. What was the original price of the car?

4) Natural fruit juice contains 80% water. In concentrating the juice, 75% of the water is removed. What is the percentage of water in the concentrated juice?

5) The yearly changes in population in a town for four consecutive years were, respectively 20% increase, 20% decrease, 20% increase, 20% decrease. What is the net percentage change over the four years to the nearest percent?
Okay for Q1 10% of 350ml is just 35 ml but now what you have to do is to add water so that your 35ml that you had at the start is just 8%. Now this one can be done in two steps.

1. Find what is an eighth of 35ml and then multiply by 100 to get the new amount of cordial drink in the jug
2. Take away 350 which is the initial amount of drink in the jug to find the amount of water added.

With Q2 you are just doing the same question as Q1 but just a change of numbers so I encourage you to try this one on your own given the scaffold for Q1.
 

5uckerberg

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For Q4 this is my interpretation of it.

Since you have the juice and the water with 80% water and 20% juice. Well if 75% of the water is removed normally it would be 60% water removed but because there are two elements there the amount of water removed is half of that amount so in turn only 30% of water is removed and therefore in the end we have 50% water left over in the concentrated juice.
 

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