Question

An alloy contains 30%copper,42% nickel and rest zinc, find the mass of zinc in 2 kg of alloy.

Answer 1

$\sf\large\underline{Given:}$

• $\rm{The\:mass\:of\:copper=30\%}$
• $\rm{The\:mass\:of\:nickel=42\%}$
• $\rm{Total\:mass\:of\:alloy=2kg}$

$\sf\large\underline{To\: Find:}$

• $\rm{The\:mass\:of\:zinc=?}$

$\sf\large\underline{Solution:}$

• At first calculate the mass of zinc out of alloy than calculate separately the mass of other metals ]

$\rm{\implies The\:mass\:of\:zinc=100-(30+42)}$

$\rm{\implies The\:mass\:of\:zinc=100-72}$

$\rm{\implies The\:mass\:of\:zinc=28\%}$

• Now, find out the mass of all metals here]

$\rm{\implies The\:mass\:of\:zinc=2000\times \dfrac{28}{100}}$

$\rm{\implies The\:mass\:of\:zinc=20\times 28}$

$\rm{\implies The\:mass\:of\:zinc=560g\:or\:0.560kg}$

$\rm{\implies The\:mass\:of\: copper=2000\times \dfrac{30}{100}}$

$\rm{\implies The\:mass\:of\: copper=20\times 30}$

$\rm{\implies The\:mass\:of\: copper=600g\:or\:0.600kg}$

$\rm{\implies The\:mass\:of\:nickel=2000\times \dfrac{42}{100}}$

$\rm{\implies The\:mass\:of\:nickel=20\times 42}$

$\rm{\implies The\:mass\:of\: nickel=840g\:or\:0.840kg}$

$\sf\large{Hence,}$

$\rm{\implies The\:mass\:of\:zinc=560g\:or\:0.560kg}$

$\sf\large\underline{Verification:}$

$\rm{\implies The\:mass\:of\:C+N+Z=2kg}$

$\rm{\implies 600g+840g+560g=2kg}$

$\rm{\implies 2000g=2kg}$

$\rm{\implies 2kg=2kg}$

$\sf\large{Hence,\: Verified:}$

Answer 2

the mass of zinc = 100 - (30 + 42)

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 100 - 72

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 28 %

mass of zinc = 2000 x 28/100

⠀⠀⠀⠀⠀⠀⠀⠀⠀= 20 x 28

⠀⠀⠀⠀⠀⠀⠀⠀⠀= 560g

the mass of copper = 2000 x 30/100

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 20 x 30

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 600g

the mass of nickel = 2000 x 42/100

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 20 x 42

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 840g

mass of c + n + z = 2 kg

560 + 600 + 840 = 2 kg

2000g = 2kg

2kg = 2kg