Arithmetic Flashcards
What fraction is equal to 0.06?
6/100
What is the value of 4/10 + 3/100
43/100
A store stocked 150 cans of popcorn, 72 cans were sold. What percent of popcorn were sold?
48%
8/3, 2.28, 10/12, 0.199 - What number has the greatest value?
8/3
What is 25% of 130?
1) Find 10% of 130:
10% of 130 is 13 (just move the decimal one place to the left).
2) Find 5% of 130:
5% is half of 10%, so half of 13 is 6.5.
3) Combine to get 25% (which is 20% + 5%):
4) 20% is twice 10%, so 13 (step 1) × 2 = 26 (13×2=26)
5) Add 5% (6.5 - step 2) to 20% (26 - step 4):
26 + 6.5 = 32.5
So, 25% of 130 is 32.5
What is equivalent to 8/25?
1) Recognize the denominator as a factor of 100:
Since 25 × 4 = 100 you can multiply both the numerator and the denominator by 4 to make the denominator 100.
2) Perform the multiplication:
8 × 4 32
—- = ——
25 x 4 100
3) Convert to a decimal
32
—— is 0.32
100
So, 8/25 is equivalent to 0.32
If Tim got 25% of the total and made $445, how much did Tina get?
Pie Graph ppx insert.
Tina - 30%
Tim - 25%
Jake - 20%
Joe - 20%
idk.
What is
7 - 6/4
If Jack took 2/3 time to run 3 miles and Sarah ran 3 miles 2/3 faster than Jack did, how long did Sarah take to run the 3 miles?
Rank these from lowest value to increasing value
0.15 , 3/4 , 8/5 , 0.25%
12% of 8 is what number?
1) What is 10% of 8?
8 x 0.1 =0.8 0.8
2) What is 2% of 8?
8 x 0.02 =0.16 0.16
3) Add 0.8 (10%) + 0.06 (2%) together to get (12%) of 8
4) = 0.96
–> remember when adding decimals, you can put an extra zero after the 0.8 to line it up with the 6 column because extra place holders to the right of a decimal don’t matter
- If the scale on a road map is 1 inch = 150 miles, how many inches would represent 1050 miles?
a. 4
b. 7
c. 8
d. 12
1) cross, muliply, divide
1/150 = ?/1050
2) cross multiple: 1 x 1050 = 1050 then divide: 1050 / 150 = 7
–> had to use trial and error with long multiplication to find 7
3) = 7/1050
the answer is b)
- What is 2 1/2 divided by 1/2?
a. 4
b. 3
c. 5
d. 6
1) Convert 2 1/2 into an improper fraction
2 1/2 = 5/2
2) Dividing fractions is the same as multiplying by the reciprocal, so multiply 5/2 x 2/1
3) 5/2 x 2/1 = 10/2
4) put in lowest form: 10/2 = 5
–> the answer is c) 5
- Solve the following for y: 12y – 16 = 20
a. y = 2
b. y = 3
c. y = -3
d. y = 1
b) y = 3
1) move -16 over first
12y = 20 + 16
12y = 36
2) Divide both sides by 12
12y / 12 = 36 / 12
y = 2
- What is the volume of water for swimming pool that is shaped like a box and is 8 feet high, 5 feet wide, and 10 feet long?
a. 23 cubic feet
b. 140 cubic feet
c. 420 cubic feet
d. 400 cubic feet
volume = length x width x height
volume = 10 x 5 x 8
= 50 x 8
= 400
- Divide 3.3 by 0.06
a. 0.198
b. 55
c. 60
d. 198
1) get rid of the decimal by multiplying both numbers by 100:
3.3 x 100 = 330
0.06 x 100 = 6
2) Now divide 330 / 6 using long division
3) you will get 55
–> the answer is b) 55
- The population of Tigers in Bangladesh was 2000 in 1984. In 1994 it had decreased to 1,400. Find the percent decrease in population during those 10 years.
a.70%
b.80%
c.10% d.30%
1) do 2000 - 1,400 = 600
2) 600/2000 = x / 100
–> cross multiply divide to find the percent
