in the early months of some year, one site added 0.2 million new accounts everyday. At this rate how many days would be needed to add 10 million new accounts

Question

Algebra and it is very hard I need help  please. I don't  understand word problems so I will need help.

Answer 1

Word problems can be difficult. The key is to extract the information you need to answer the question it is asking.

 

"In the early months of some year, one site added 0.2 million new accounts every day. At this rate, how many days would be needed to add 10 million new accounts?"

 

The question is asking for the number of DAYS needed, at a specific RATE, to reach 10 million new accounts. A "rate" is a ratio that compares two quantities... like 50 miles PER hour, 4 batteries PER flashlight, or in this case, 0.2 accounts PER day. In shorthand, 50 miles/hour, 4 batteries/flashlight, 0.2 accounts/day.

 

I'm going to use a technique from chemistry to solve this mainly because of the units ("accounts per day"). I find it is easier to keep track of everything (ESPECIALLY for word problems, because it is so easy to set up the information incorrectly and get the wrong answer).

 --> In chemistry, we would consider the rate a "conversion factor" meaning it is a division expression that helps convert numbers with one unit into numbers of another unit (from " # of new accounts" to "# of days"). 

 

10 million accounts x RATE = # days

 

Here, it is important that the unit you want to find is in the numerator of your conversion factor (or rate), because we will cancel the "old" unit (new accounts) so we are left with the new unit (# days)

 

10 million accounts x (day / 0.2 million accounts) = 50 days

 

We can reduce 10 and 0.2, since 0.2 goes into 10 50 times [(10/0.2)=50]. This changes the denominator to 1, essentially making it unimportant (we don't always say 50/1=50, we just say 50), and similarly, the units "million accounts" cancels out. So, multiplying across yields 50 days as your answer.

 

50 million accounts x (day / 1 million accounts) = 50 days

 

I hope this did not confuse you! This is just a different way of approaching this kind of problem. The difficulty I always have with word problems is making sure I'm setting the equation up correctly given the words and circumstances the problem tells me. If you can keep track of the units it makes a little more sense.