Ratio, fraction, decimal & percentage - Wiki

  • #ratiofractiondecimal
    • Cheryl and Kenny shared some marbles. Cheryl had `2/5` the number of marbles Kenny had. What was the ratio of the number of marbles Cheryl had to the number of marbles Kenny had to the total number of marbles they had?
      • #ratiofractiondecimal&percentage

         C : K

         2 : 5

        Total = 2 + 5 = 7

        C : K : Total

        2 : 5 : 7

    • There are some cows and goats on a farm. `1/5` of the number of cows is equal to the `5/8` of the number of goats. There are 34 more cows than goats. How many goats are there on the farm? Ans: _BLANK_
      • #ratiofractiondecimal&percentage

        `1/5`  of cows = `5/8`  of goats

        `5/25`  of cows = `5/8`  of goats

        Ratio of cows to goats

        25:8

        Difference

        25u - 8u = 17u

        17u = 34

        1u = 34 `-:` 17 = 2

        No. of goats

        8u = 8 `xx` 2 = 16
              

    • A third of Gabriel's mass is thrice that of Helen's mass. Express Helen's mass as a fraction of their total mass.
      • #ratiofractiondecimal&percentage 

        `1/3` u of Gabriel's mass = 3u of Helen's mass   

        1u of Gabriel's mass = 9u of Helen's mass

        G: H

        3 : `1/3`

        9 : 1

        Total mass = 9u + 1u = 10u

        Helen's mass as a fraction of total mass

        `1/10`   

    • James used `4/7` of his screws and `3/5` of his nails to construct a wooden cupboard. In the end , he had an equal number of screws and nails left. Given that James had a total of total of 145 screws and nails at first, how many nails did he use to construct the wooden cupboard? Ans: _BLANK_ [3]
      • #ratiofractiondecimal&percentage

        Fraction of screws left

        `7/7`  - `4/7`  = `3/7`

        Fraction of nails left

        `5/5`  - `3/5` = `2/5`

        `3/7`  of S = `2/5`  0f N

        `6/14`  of S = `6/15` of N

        Ratio of S:N

        `->` 14:15

        Total units = 14 + 15 = 29u

        29u = 145

        1u = 145 `-:` 29 = 5

        Total amt. of nails

        15u = 5 `xx` 15 = 75
                     

            

    • Sarah has some mystery and comic books. The number of mystery books is `2/3` the number of comic books. What is the ratio of the number of mystery books to the total number of books she has?
      • #ratiofractiondecimal&percentage

        M : C : Total

        2 : 3 : 5

        Ratio of no. of mystery books to the total

        2 : 5