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• Pre algebra
• Percents, Ratios and Propotions
• Use proportions to solve for an unknown quantity

# Use proportions to solve for an unknown quantity

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•  Question 1: 1 pts To make $20$ pancakes you have to use $4$ eggs. How many eggs are needed to make $100$ pancakes?
 $5$ $10$ $20$ $30$
•  Question 2: 1 pts Find the length of a photograph whose width is $49$ inches and whose proportions are the same as a $7- \mbox{inch}$ by $9-\mbox{inch}$ photograph.
•  Question 3: 1 pts If $3$ pounds of apple cost $\$0.89$what is the cost of$15$pounds of apples at the same rate. $\$4.75$ $\$3.75\$4.45$ $\$3.45$•  Question 4: 1 pts A bookstore offers$5$textbooks for$\$135.$ How much will it cost a teacher to purchase $32$ textbooks for her class?
 $\$964\$864$ $\$764\$664$
•  Question 5: 1 pts The scale on a map is given as $9 \mbox{centimeters}$ to $4.5 \mbox{kilometers.}$ How far apart are two towns if the distance between this two towns on the map is 16 centimeters?
 $10 \mbox{kilometers}$ $9 \mbox{kilometers}$ $8 \mbox{kilometers}$ $7 \mbox{kilometers}$
•  Question 6: 2 pts If $\dfrac{1}{2}$ pound of meat sells for $\$4.50$, how much meat can be bought for$\$31.5$?
•  Question 7: 2 pts An electric pole, $14$ metres high, casts a shadow of $10$ metres. Find the height of a tree that casts a shadow of $15$ metres under similar conditions.
 $x=21$ $x=20$ $x=19$ $x=18$
•  Question 8: 2 pts If the weight of $12$ sheets of thick paper is $40$ grams, how many sheets of the same paper would weigh $2\dfrac{1}{2}$ kilograms?
 $x=600$ $x=750$ $x=850$ $x=900$
•  Question 9: 3 pts A car travels $540 \mbox{km}$ at an average speed of $108 \mbox{km/h.}$ How long will it take a truck to travel the same distance if its speed is $\dfrac{1}{3}$ that of the car?
 10 hours 15 hours 20 hours 25 hours
•  Question 10: 3 pts One piece of pipe 21 meters long is to be cut into two pieces, with the lengths of the pieces being in a 2 : 5 ratio. What are the lengths of the pieces?
 4 meters and 17 meters 7 meters and 14 meters 6 meters and 15 meters 5 meters and 16 meters
•  Question 11: 3 pts In the United States, 21out of every 100 people are under the age of 15. In a town of 20 000 people, how many people would you expect to be under the age of 15?
•  Question 12: 3 pts Kumar lives in Croatia, and is visiting relatives in India. The current exchange rate is one Euro to $80.45$ Indian rupees . He wants to buy a gift for them, which costs $3 759$ Indian rupees. How many Euros will this gift cost him? (State your answer accurate to two decimal places.)
 $45.99$ $46.70$ $46.71$ $46.72$