Problem 4)
There are 160 students and 100 boys (of that group) so there must be 160-100 = 60 girls.
The ratio of girls to boys is going to be 60:100. All I did here was write the number of girls first followed by a colon and then the number of boys.
After this ratio is set up, we need to reduce it as much as possible. Divide both parts by the GCF 20 to get
60/20 = 3
100/20 = 5
So the ratio 60:100 turns into 3:5
Final Answer is 3:5
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Problem 5)
"unit price" means "cost for one item (aka a unit)"
4 candy bars sell for $2.12 which means we have the ratio 4:2.12
The first number is the number of bars, the second is the total cost
Note again how there's a colon to separate the values
To find the cost of 1 bar, we divide both parts by 4. We do this since 4/4 = 1
So,
4/4 = 1
2.12/4 = 0.53
The ratio 4:2.12 turns into 1:0.53 after dividing both parts by 4
The ratio 1:0.53 means that 1 bar costs $0.53 or 0.53 dollars or 53 cents
The most likely answer to enter into the blank is 0.53