7th Grade Math (percent) Problems..please Help Me T_t~?
Posted by admin | Posted in Blogging | Posted on 09-11-2009
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Hello. I’m in 7th grade. Can you please tell me the answer for these questions please~T_T
I tried to do it but i couldn’t … If you can explain to me shortly that would be really great too~! Thank You So Much:D!
1.Write 4.6 as a percent <- is it 46%?? I'm not sure T_T
2. Write 5/12 as an equivalent percent
3. The net price of a certain article is $306 after successive discount of 15% and 10% off the marked price. What is the marked price?
4. If a merchant makes a profit of 20% based on the selling price of an article, what percent does the merchant make on the cost?
5. A certain radio costs a merchant $72. At what price must the merchant sell this radio in order to meke a profit of 20% of the selling price?
6. A badeball team has won 40 games out of 60 played. It has 32 more games to play. How many of these must the team win to make its record 75% for the season?
7. If prices are reduced 25% and saled increase 20%, what is the net effect on gross receipts?
1. 4.6 as a percent.
To change a number into a percentage, you multiply the number by 100% or simply move the decimal place two spaces to the right (don’t forget your zero’s) and add a percent sign.
4.6 = 460%
2. 5/12 as a percent
Divide 5 by 12. Once you get that number, do what I did above.
5/12 = 0.416666… = 41.667%
3. 15% off a $306 item which is 10% off.
First the 10%. When an item is 10% off, you’re paying 90% of the item’s original price. So we want to find 90% of $306. To do that, change the percentage into a workable number by doing the opposite of what I did before by moving the decimal place two places to the LEFT. This turns 90% into 0.9. Multiply this number by $306. Once you get that, do the same with the 15% off, which means you’re paying 85% of the item’s price so multiply .85 by the new number.
$306 * 0.9 = $275.40
$275.40 * 0.85 = $234.09
4. The merchant must buy something for less than he is selling it for to make a profit. The 100% of the price he is selling it for is split into 1) how much he payed for it, since he is making a profit it’s going to be cheaper than what he’s selling it for, and 2) how much he is profiting. If he makes a 20% profit then 100% – 20% is how much he had to pay for it. 80% of the cost is however much the merchant bought it for.
5. If he wants to make a 20% profit then the $72 needs to be (100%-20%) 80% of the cost he sells it for. To find out what 100% of the price is, you set up some ratios.
($72 / 80%) = ($x / 100%)
7200 = 80x <–cross multiply
x = $90 <– and divide.
6. The total games played will be 60+32=92. The winning ratio must be 0.75 (75% converted into a number). So if we divide the target number of total wins by 92 we should get 0.75. That means we need to find x, the number of wins in the remaining 32 in this equation:
(40 + x) / 92 = 0.75
40 + x = 69 <– cross multiply
x = 29 <– subtract.
7. When prices are reduced 25% that means customers pay 75% of the original cost. When sales increase 20% it means sales are at 120% of what they originally were. Change these percentages into workable numbers and multiply.
0.75 * 1.20
0.90
So gross sales are at 90% of what they were originally.
1. 460%.
Remember, percent simply means parts per hundred, or hundredths. In our decimal system, the second decimal place to the right of the decimal point is the hundredths place (0.0X). So 0.05 is 5%. 0.11 is 11%, etc. 0.256 is 25.6%.
2. 41.7%.
Convert 5/12 to a decimal number. Five divided by twelve is 0.4166666… = 0.417.
The hundredth’s place is where the “1″ is, so we get 41.7%.
3. $400
The net price ($306) represents 90% of the price after the second markdown (10%). So $306 = 0.90x where x was the price after the 10% markdown. x = $306 / 0.90 = $340.
This price represents 85% of the original marked price before the 15% markdown.
$340 = 0.85x; x = $340 / 0.85 = $400.
4. 120%
If the cost of the item is 100% and the dealer makes a profit of 20%, then he’s taking in 120% of the cost.
5. $90
Let x be the selling price. His profit is the difference between x and his cost, which is $72.
So profit = x – 72. He wants to make a profit (x – 72) equal to 20% (0.20) of the selling price (x).
x – 72 = 0.20 x
0.80 x = 72
x = 90
6. 29
Let x = games the team must win. Since they already have 40 wins, their final wins will be 40 + x. They want this total to be 75% (0.75) of the total number played (60 + 32 = 92).
40 + x = 0.75 (92)
40 + x = 69
x = 29; They need to win 29 of their last 32? Good luck!!!
7. -5% seems like too easy an answer.
1. 4.6×100=460%
2. For fractions, convert to decimal (5 divided by 12) then multiply by 100. 5/12 =.4166666666etc, x 100= 41.6%
3. I had to try this out, but it doesn’t matter which way you do it (10% first, then 15% or 15% first then 10 %), the original price of the item is $400. Here’s how I did it:
Current price=price after 10% markdown, so it is 90% of prior cost (306=90%X, X=306/0.9) which is $340.
$340 is price after 15% markdown, you do the same thing, $340=85%X, X=340/0.85), which is $400.
Do you see how I did that? If $306 is the final price after a 10% markdown, it is 90% of that prior price.
4. This kind of doesn’t make sense (sorry).
5. Merchant wants to sell radio so as to make 20% profit. Therefore, the cost of the radio will be 120% (getting back 100% of your cost would mean that you break even, don’t make or lose money) of 72, which is the same as saying 72-1.2, which is $86.40
6. Total games=60 (games already played) + 32 yet to go=92 games. To have a 75% win record, you determine
75% of 92=0.75×92=69. They’ve won 40 games, already, so they need 29 more wins.
7. I honestly don’t know this one. My knee jerk response is that you will still have a 5% loss (your prices went down 25% but you only increased sales by 20%). I’m not sure what they mean by “net effect on gross receipts”.