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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.)
    $45.99$
    $46.70$
    $46.71$
    $46.72$

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