Question

An alloy is made of copper and iron by weight. 42% of it is copper and the rest is iron. If the alloy weights 55 kg, find the weight of copper and iron

Answer 1

Answer:

percent of iron in alloy= 100-42 = 58%

weight of the iron = 55×58÷100= 31.9

weight of iron= 31.9 kg

weight of copper= 55-31.9=23.1

weight of copper = 23.1

Step-by-step explanation:

[ I'm not sure but I think this is right ]

Answer 2

Answer: copper = 23.1 kg

             iron = 31.9 kg

Step-by-step explanation:

copper = 42% of 55

             = 42/100 * 55

            = 42/20 * 11

           = 21/10 * 11

          = 231/10

          = 23.1 kg

  so iron = 100% - 42%

             = 58%

so

58% of 55

= 58/100 * 55

= 58/20 * 11

=31.9 kg