Bosco

Ms. Lee has 12 boxes of crayons. Next year, she plans to buy 250% more boxes. How many boxes will she have in all?     

12 + (2.5)(12)  =     

12 + 30            =  42     

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To win a game with a fair coin, you must flip n+1 heads in a row, where is the total number of tails flipped so far. So if your first flip is heads, you win and the game is over; if your first flip is tails but your next two in a row are heads, you win and the game is over; and so on. What is the probability that you win by flipping one head? Express your answer as a common fraction.     

It has to be heads on the first flip, so  1 / 2     

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Jacob is constructing a fish tank that is 1.2 m long, 0.6 m wide, and 0.4m high. How much glass will he need to make it? (Note: There will be no glass on the top.)    

  1.2 x 0.6 x 1  =  0.72   bottom     

  1.2 x 0.4 x 2  =  0.96   front and back     

  0.6 x 0.4 x 2  =  0.48   left and right ends     

               total  =  2.16 m²     

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In the figure PQ is parallel to RS. The length of QT is 4 cm; the length of TS is 6 cm; the length of PQ is 10 cm. What is the length of RS?​     

     TS : TQ  =  RS : PQ     

        6 : 4     =  RS : 10     

        6 / 4     =  RS / 10     

      60 / 4     =  RS     

             RS  =  15     

_.     

sin = opp / hyp     

sin(43)  =  240 / x     

x  =  240 / sin(43)     

x  =  240 / 0.6820     

x  =  351.9062 cm  converts/rounds to  3.5 m     

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Among all rectangles that have a perimeter of 84, find the dimensions of the one whose area is largest. Write your answers as fractions reduced to lowest terms.     

The rectangle that has the highest ratio of area to perimeter is a square.     

Therefore, when its perimeter is 84, the sides of that square are 21x21.     

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