3rd and 4th Grade, December, 2017

    A.1161. Three children were looking at the birds in a 3-level bird cage in a pet store. Luca said that the bird on the top level is a canary and that the bird in the middle level is a finch. Flora said that there is a parrot in the middle level, and a canary on the bottom. Kim said that the bird on the top is a canary and the one on the bottom is a parrot. What kinds of birds were on the bottom, in the middle and on the top level, if each child was right about one of the birds and wrong about the other?

    A.1162. There are 24 parrots in a bird cage. The color of the beak and the tail feather of every one of them is either yellow or red. 13 of them have red beaks, 12 of them have yellow tail feathers, and 8 of them have both red beaks and yellow tail feathers.  

    a) How many parrots have yellow beaks and yellow tail feathers?  

    b) How many parrots have red beaks and red tail feathers?  

    c) How many parrots have yellow beaks and red tail feathers?

    A.1163. There are 4 kinds of rodents for sale in the Pet Store. There are 2 more Guinea pigs than jumping mice, 3 more white mice than hamsters. There are a total of 60 Guinea pigs and hamsters, and 3 times as many hamsters as Guinea pigs. How many rodents are there all together in the store?

    A.1164. Camille was looking at the fish in the tanks. 3 zebras and 8 neon fish cost $43.90, 5 zebras and 10 neon fish would cost $60.50 . She decided to buy 7 zebras and 7 neon fish. How much did she have to pay?

    A.1165. In the zoo they are making the frame of a solid cage with a rectangular base from heavy wires. The length of the middle-sized edge of the solid is half as long as the longest edge, and twice as long as the shortest edge. They needed 784 cm of wire to make the edge frame of this cage. How long are the edges?

    A.1166. Oliver loves to swim in a lake. There are buoys placed 30 meters apart in a straight line. Oliver started swimming from the first buoy to the 6th. He used breast stroke for the first half of the way, used free style for a distance 10 meters more than a third of the way, and used back stroke for the rest of the way. How much more did he swim using breast stroke than using back stroke?

    A.1167. Sahil loves to fish. On his last vacation he caught a total of 46 fish: carp, trout, and catfish. He caught a total of 28 trout and catfish, and 3 less trout than carp. How many of each kind of fish did he catch?

    A.1168. Amaya had an ice cream every day after lunch on her family’s last vacation. There were four kinds of ice cream at the parlor: chocolate, vanilla, strawberry and lemon. Amaya asked for a total of 4 scoops every day from two flavors of her choice for the day. Was she able to have a different combination every day of the 10-day vacation if the order of the scoops is not important?

    Please send your solutions here.

    The Sharma Kamala Educational Trust is sponsoring the participation of students from India. So, if you are a student living in India, please, send your solutions to: Group A from India

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