Problem solving two: A cereal bar has 4.5g protein, 10g fat, 67g carbohydrate per...

[odcruzjr13]

Can anyone help me to show the solution of this problem solving please many thanks in advance for your help!

1. "A cereal bar has 4.5g protein, 10g fat and 67g carbohydrate per 100g. 100g contains 370kcal, and 6.4mg of iron , which provides roughly 45% of the recommended daily allowance (RDA) of iron for a healthy adult. Approximately how many 37g cereal bars would you have to eat to get 100% RDA of iron?" Answer: 6 bars


2. "A cereal bar has 4.2g protein, 9.4g fat and 63g carbohydrate per 100g. 100g contains 340kcal and 6.0mg of iron which provides roughly 40% of the recommended daily allowance (RDA) of iron for a healthy adult. Approximately how much protein is in one cereal bar weighing 42g (to one decimal place)"
Answer: 1.8g

3. A 400g tin of soup has an energy value of 256kcal and contains 1.6g of sodium. The recommended daily intake (RDI) of calories for a female per day is 2 000kcal. What is the energy value of a 150 gram serving of soup? Answer 96kcal

Please help me on how did they manage to get the answer, i just need the calculation solution please. Many thanks in advance for the help.

 

[ksdhart]

1. "A cereal bar has 4.5g protein, 10g fat and 67g carbohydrate per 100g. 100g contains 370kcal, and 6.4mg of iron , which provides roughly 45% of the recommended daily allowance (RDA) of iron for a healthy adult. Approximately how many 37g cereal bars would you have to eat to get 100% RDA of iron?" Answer: 6 bars

To make it a bit simpler, we can assume that the daily recommended dose is 100g. Then how many grams of iron are in the 100g cereal bar (hint: 45% of 100)? Since "percent" literally means "per hundred," what percentage of 100g is 37g? So how much iron is in the 37g bar? Now, given that amount, now many bars would you need to make your daily allowance of 100g of iron?

2. "A cereal bar has 4.2g protein, 9.4g fat and 63g carbohydrate per 100g. 100g contains 340kcal and 6.0mg of iron which provides roughly 40% of the recommended daily allowance (RDA) of iron for a healthy adult. Approximately how much protein is in one cereal bar weighing 42g (to one decimal place)"
Answer: 1.8g

You're told how much protein is in a 100g bar, so use the same strategy used in part of #1. What percentage of 100g in 42g? So how much protein is in a 42g bar?

3. A 400g tin of soup has an energy value of 256kcal and contains 1.6g of sodium. The recommended daily intake (RDI) of calories for a female per day is 2 000kcal. What is the energy value of a 150 gram serving of soup? Answer 96kcal

This one's a little more difficult, but it shouldn't be too bad. You're told the Calories (kcal) in 400g of soup. So how many Calories are in 150g of soup? As a hint, consider an intermediate step: How many Calories are in 100g of soup?

 

[stapel]

Can anyone help me to show the solution of this problem solving please many thanks in advance for your help!

The best way we can help is after we see what you've tried, so we can see where things are going sideways. This is why you were asked, in the "Read Before Posting thread that you read before posting (right?).

1. "A cereal bar has 4.5g protein, 10g fat and 67g carbohydrate per 100g. 100g contains 370kcal, and 6.4mg of iron , which provides roughly 45% of the recommended daily allowance (RDA) of iron for a healthy adult. Approximately how many 37g cereal bars would you have to eat to get 100% RDA of iron?" Answer: 6 bars

If each 100 grams has 45 of the units (of iron) that you need, then how much is in one gram? (Hint: Divide, or just move the decimal point.)

Then how many grams do you need, in order to get 100 units (that is, the full complement) of iron? (Hint: Divide.)

If each bar is 37 grams, then how many bars do you need? (Hint: Divide.)

The others work similarly. If you get stuck, please reply showing your work so far. Thank you!