Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Fiber X cereal is 55% fiber. Fiber Max cereal is 70% fiber. [#permalink]
29 Aug 2018, 16:18

Expert's post

00:00

Question Stats:

53% (01:18) correct
46% (02:11) wrong based on 13 sessions

Fiber X cereal is 55% fiber. Fiber Max cereal is 70% fiber. Sheldon combines an amount of the two cereals in a single bowl of mixed cereal that is 65% fiber. If the bowl contains a total of 12 ounces of cereal, how much of the cereal, in ounces, is Fiber X?

Re: Fiber X cereal is 55% fiber. Fiber Max cereal is 70% fiber. [#permalink]
31 Aug 2018, 02:43

I am sorry, I need have my head wraped around such type of question. would highly appriciate is someone can share a link to a video link to these type of questions.

Re: Fiber X cereal is 55% fiber. Fiber Max cereal is 70% fiber. [#permalink]
15 Oct 2018, 09:56

Use the weighted average formula to get the ratio of Fiber X to Fiber Max: [0.55X+0.70m][/x+m] = 0.65 where x is the amount of Fiber X and m is the amount of Fiber Max. This is not that different from the regular average formula—on the top, there is the total amount of fiber (55% of Fiber X and 70% of Fiber Max), which is divided by the total amount of cereal (x + m) to get the average. Simplify by multiplying both sides by (x + m): 0.55x + 0.70m = 0.65(x + m) 0.55x + 0.70m = 0.65x + 0.65m To simplify, multiply both sides of the equation by 100 to eliminate all the decimals: 55x + 70m = 65x + 65m 55x + 5m = 65x 5m = 10x m/x= 1/2 Since m and x are in a 2 to 1 ratio, 2/3 of the total is m and 1/3 of the total is x. Since the total is 12 ounces, Fiber X accounts for (12) = 4 ounces of the mixed cereal.

Re: Fiber X cereal is 55% fiber. Fiber Max cereal is 70% fiber. [#permalink]
15 Oct 2018, 09:56

One shortcut to this procedure is to note that the weighted average (65%) is 10% away from Fiber X’s percent and 5% away from Fiber Max’s percent. Since 10 is twice as much as 5, the ratio of the two cereals is 2 to 1. However, it is a 2

greprepclubot

Re: Fiber X cereal is 55% fiber. Fiber Max cereal is 70% fiber.
[#permalink]
15 Oct 2018, 09:56