Ratios
Mrs. Ice puts 2 pencils and 5 pens in each class pencil pouch. There 56 total writing tools. How many pencils and how many pens are there in all?
pencils pens total
2 5 7
16 (x8) 40 (x8) 56 (x8)
16 pencils
40 pens
5 shovels of sand are mixed with 4 shovels of gravel to make cement.
How many shovels of gravel are needed for 45 shovels of sand?
36 shovels of gravel
If 10 bags of Hot Cheetos cost $3.50, then what is the price per bag?
$0.35
What is 9/75 written in simplest form?
3/25
45 is 25% of what number
180
There are 75 mice in a cage. The ratio of pink mice to white mice is 2:3. How many white mice are in the cage?
pink white total
2 3 5
30 (x15) 45 (x15) 75 (x15)
45 white mice are in the cage
Select all of the trips that will take 3 hours.
A. Drive 70 miles per hour between Dallas, Texas and Austin, Texas which are 200 miles apart.
B. Walk 3 miles per hour to school which is 9 miles away.
C. Take a train going 90 miles per hour from Atlanta to Nashville which are 270 miles apart.
B & C
A is incorrect because
mi. 70 = 200 mi.
hr 1 hr
1200 x 1 = 1200 1200 / 70 = 2.9 hours
B is correct because
mi. 3 = 9 mi.
hr. 1 hr
9x1=9 9/3 = 3 hours
C is correct because
mi. 90 = 270 mi.
hr. 1 hr.
270 x 1 = 270 270/90 = 3 hours
Tommy runs 5 miles in 15 min.
Andre runs 6 miles in 18 min.
What is each boy's speed per minute?
What is each boy's pace (minutes per mile)?
Who is faster?
Tommy:
speed = 5 miles / 15 min. = 0.3 miles per min.
pace = 15 min. / 5 miles = 3 min. per mile
Andre:
speed = 6 miles/ 18 min. = 0.3 miles per min.
pace = 18 min. / 6 miles = 3 min. per mile
Neither is faster - both their speed and pace =
Riddle:
1) I am a whole number percent less than 100.
2) In decimal form, my tenths place digit is a 7.
3) In simplified fraction form, my denominator is a 4.
What percent am I?
75%
In the Crossroads parking lot, 35% of the cars are white. There are 120 cars in the parking lot. How many cars are NOT white?
78 cars are NOT white
Method 1
35% = part
100 120 whole
35 x 120 = 4200 4200/100 = 42 cars ARE white
120 - 42 white cars = 78 cars are NOT white
Method 2:
100% - 35% white = 65% are not white
65% =
100 120
65 x 120 = 7800 7800 / 100 = 78 cars are NOT white
True or False?
If there are 14 red Skittles, 15 green Skittles, and 21 purple Skittles, then the ratio of green to total is 3:10.
TRUE
15:50 simplifies to 3:10 (divide by 5)
Michael's Fresh Eggs transports its eggs in crates. It takes 2 trucks to carry 80 crates.
What is the number of crates that 5 trucks can carry?
200 crates
Ian hikes 2.25 miles in 1⁄2 an hour. If he hikes for 7 hours, how far will he have gone?
mi 2.25 = mi.
hr 0.5 7 hr
2.25 x 7 = 15.75 15.75/.5=31.5 miles
31.5 miles
The usual price of shoes is $75.
The store is running a sale and the shoes are 80% of their normal price.
What is the sale price?
$60
Maureen made an 88% on her last math test.
She answered 22 problems correctly. How many problems were on the test?
25 problems on the test
Tyler is 5.5 feet tall. How many inches tall is Tyler?
(1ft = 12 in.)
66 inches
Avi can walk 2 miles in 40 min.
What is the amount of time it will take him to walk 4 miles?
80 minutes
Find the unit rates for the following problems (calls per 1 hour):
27 calls in 9 hours
3 calls per hour
287/100
= (please write the decimal form)
2.84
True or false: 20% of 512 = 1/4 of 512
FALSE
In the name "Our Lady of the Southern Cross College", what is the simplified ratio of vowels to consonants?
(vowels: a, e, i, o, u)
12 : 20 simplifies to 3 : 5
Which is the better buy?
36 books for $250 or 30 books for $209?
36 books for $250
Find the TWO unit rates for 5 calculators for $105
dollars per calculator
AND
calculator per dollar): (round to the nearest hudredth)
$105/5 = $21 per calculator
AND
5 calc./ $105 = .05 calculators per dollar.
What percentage is 36 kg of 90 kg?
40%
A computer is on sale for 20% off. If the original price is $600, what is the sale price of the computer?
$480