Percents and problem solving Help please!?

Question

1: William worked 195 km in 12 days. At this rate, how far would he walk in 36 days?
585 km
473 km
691 km
699 km


2: To make biscuits, Juanita uses 5 cups of flour to 1 cup of milk. If she uses 3 cups of milk, how many cups of flour will she use?
12 cups
14 cups
13 cups
15 cups


3: The average human heart beats at 72 beats per minute. How many times does it beat in 25 seconds?
26 times
30 times
1800 times
200 times


4: Based on the information above, how many times does it beat in an hour?
4682 times
4296 times
4320 times
5497 times


5: If Joseph can shape 3 surfboards in 50 minutes, how many surfboards can he shape in 5 hours?
15 surfboards
17 surfboards
83.3 surfboards
18 surfboards


6: In translating equations, the word "is" means _____.
multiply
equals
a variable
add


7: To convert a decimal to a percent we move the decimal _____ places to the ______ and include the percent symbol.
two; left
one; right
two; right
one; left


8: Write an equation for this statement:
5% of what number is 175?

.05(n) = 175
.05 = 175n
5n = 175
5n = 175n


9: Solve for n in the equation above.
.03
170
3500
35


10: The old box of oatmeal cookies weighed 12 oz. The new box is 15% larger. What is the new size?
13 oz
13.8 oz
14 oz
14.3 oz


11: The local sports complex just added another level of seating which has increased the seating capacity by 18%. If it used to seat 9,300 people, how many will it seat now?
11,240
11,154
10,974
12,273


12: Two years ago, the children at the winter mitten drive collected 568 pairs of mitten and gloves. Last year, the children collected 325 pairs for the needy. This year, there was a 4% increase in the collection from last year.
How many pairs did they collect this year?
329
338
398
342


13: An item that usually sells for $65.00 is marked down 25%. What is the new price?
$46.35
$48.75
$49.52
$50.82


14: The local sports complex added another section of seating. This increased the seating capacity by 3%. If it used to seat 10,300 people, how many will it seat now?
9,991
10,373
11,275
10,609


15: Homes may increase in value for a variety of reasons. A certain house that used to cost $150,000 now costs 4% more. What is the new value?
144,000
156,000
162,000
145,223


16: Since they were selling less cars, Modern Car Sales reduced the prices of all their vehicles by 3%. On a car that used to cost $25,000, what is the new price?
$23,900
$24,170
$24,250
$23,385


17: In a certain voting district, there was an 8% decrease in the number of voters from the last election. If 460 people voted last election, how many voted in this election (round to the nearest whole number)?
416
420
423
442


18: 280 is increased to 460. What's the percentage increase? Round the percent to the tenths place.
58.2%
59.4%
67.2%
64.3%


19: Our grocery shopping bills in May totaled $400. In June, that number increased to $450. What's the percentage increase?
12.5%
13%
14.3%
15.2%


20: Last year, there were 36 students with 4.0 GPAs in Ms. Barrons class. This year, there are 45. What's the percentage increase.
20%
25%
29%
30%

Answer 1

You are asking a lot to be posting 20 problems in one question, don't you think?

19. 12.5%
20. 25%

Answer 2

Tricky problem, simple answer. Let's say A and B are amounts, and P is percent. The standard formula (the only one you need to remember) is that P (in percent) = A/B x 100. You can derive all the other questions from this one. You must arrange the formula so that the unknown is on the left, and the two knowns on the right. If P is the unknown you're in good shape with the above formula. If the unknown is not P but A, then you multiply both sides of the standard formula by B and divide by 100, and rearrange so the A is now on the left => A = P x B / 100 If the unknown is not P or A but B, then you multiply both sides of the standard formula by P and divide by B, and rearrange so that B is on the left => B = A/P x 100. Try it with a pencil and paper so you get it all worked out. Here are the answers to your quiz: Question 1: What is P percent of B (given A and B)? A (= P percent of B) = P/100 x B Question 2: A is P percent of what (given A and P)? B (= what A is P percent of) = A/P x 100 Question 3: A is what percent of B (given A and B)? P (= the percent that A is of B) = A/B x 100 So you see all three are from the same initial formula or from rearranging its terms so that the unknown is on the left. Here are the numerical examples: Q39: Formula = Question 2 above. B = A/P x 100 = 3/60 x 100 = 5 Q41: Same formula as Q39 B = A/P x 100 = 40.8/24 x 100 = 170 Q43: Standard formula P = A/B x 100 = 3/15 x 100 = 20% Q45: Standard formula P = A/B x 100 = 0.3/2.5 x 100 = 12% Good luck with this! Regards,

Answer 3

1: William worked 195 km in 12 days. At this rate, how far would he walk in 36 days?
585 km
473 km
691 km
699 km

Ans: 195 X 36/12 = 195 X 3 = 585 km

2: To make biscuits, Juanita uses 5 cups of flour to 1 cup of milk. If she uses 3 cups of milk, how many cups of flour will she use?
12 cups
14 cups
13 cups
15 cups

Ans: 5 X 3 / 1 = 15 cups


3: The average human heart beats at 72 beats per minute. How many times does it beat in 25 seconds?
26 times
30 times
1800 times
200 times

Ans: 72 X 25/60 = 30 times

4: Based on the information above, how many times does it beat in an hour?
4682 times
4296 times
4320 times
5497 times

Ans: 72 X 60 = 4320 times

5: If Joseph can shape 3 surfboards in 50 minutes, how many surfboards can he shape in 5 hours?
15 surfboards
17 surfboards
83.3 surfboards
18 surfboards

Ans: 3 X 5 X 60/50 = 18 surfboards


6: In translating equations, the word "is" means _____.
multiply
equals
a variable
add

Ans: Equals seems to be indicated


7: To convert a decimal to a percent we move the decimal _____ places to the ______ and include the percent symbol.
two; left
one; right
two; right
one; left

Ans: Two, right


8: Write an equation for this statement:
5% of what number is 175?

.05(n) = 175
.05 = 175n
5n = 175
5n = 175n

Ans: 0.05(n) = 175 where n is the number. Its magnitude is 175 X 100/5 = 3500


9: Solve for n in the equation above.
.03
170
3500
35

Ans: 3500 (see the solution above)


10: The old box of oatmeal cookies weighed 12 oz. The new box is 15% larger. What is the new size?
13 oz
13.8 oz
14 oz
14.3 oz

12 X 1.15 = 13.8 0z


11: The local sports complex just added another level of seating which has increased the seating capacity by 18%. If it used to seat 9,300 people, how many will it seat now?
11,240
11,154
10,974
12,273

Ans: 9300 X 1.18 = 10,974


12: Two years ago, the children at the winter mitten drive collected 568 pairs of mitten and gloves. Last year, the children collected 325 pairs for the needy. This year, there was a 4% increase in the collection from last year.
How many pairs did they collect this year?
329
338
398
342

Ans: 325 X 1.04 = 338 pairs


13: An item that usually sells for $65.00 is marked down 25%. What is the new price?
$46.35
$48.75
$49.52
$50.82

Ans: 65 X 0.75 = 48.75

14: The local sports complex added another section of seating. This increased the seating capacity by 3%. If it used to seat 10,300 people, how many will it seat now?
9,991
10,373
11,275
10,609

Ans: 10,300 X 1.03 = 10,609


15: Homes may increase in value for a variety of reasons. A certain house that used to cost $150,000 now costs 4% more. What is the new value?
144,000
156,000
162,000
145,223

Ans: 150,000 X 1.04 = 156,000

16: Since they were selling less cars, Modern Car Sales reduced the prices of all their vehicles by 3%. On a car that used to cost $25,000, what is the new price?
$23,900
$24,170
$24,250
$23,385

Ans: 25000 X .97 = 24250


17: In a certain voting district, there was an 8% decrease in the number of voters from the last election. If 460 people voted last election, how many voted in this election (round to the nearest whole number)?
416
420
423
442

Ans: 460 X .92 = 423


18: 280 is increased to 460. What's the percentage increase? Round the percent to the tenths place.
58.2%
59.4%
67.2%
64.3%

Ans: 460 - 280 = 180 / 280 = 9/14 = 0.643 = 64.3%


19: Our grocery shopping bills in May totaled $400. In June, that number increased to $450. What's the percentage increase?
12.5%
13%
14.3%
15.2%

Ans: 450 - 400 = 50 / 400 = 1/8 = 12.5%


20: Last year, there were 36 students with 4.0 GPAs in Ms. Barrons class. This year, there are 45. What's the percentage increase.
20%
25%
29%
30%

Ans: 9/36 = 25%

Answer 4

Build two fractions and set them equal to each other.

195 km / 12 days = x / 36 days

x = 195 km * 36 days / 12 days

Either multiply and get 7020 km-days / 12 days = 585 km

Or remove days from both numerator and denominator and divide a 12 from the 36 and from the 12 and get

195 km * 3 = 585 km


15: 1.04 / 1 = x / 150,000
150,000 * 1.04 = x
156,000 = x

Answer 5

km days
195 12

xkm 36
x195*36/12 =585km. answer