A brass metal bar is made up of copper and zinc. (Between 50% to 70% is copper.) A brass metal bar weighs 20.15 ounces. 35% of the bar is zinc. How many ounces of copper are in the bar?

The correct answer would be - 13.0975 ounces.

Explanation:

We know that brass is made up of zinc and copper. The copper part of the brass is approximately around 50 to 70% and the remaining is the zinc part.

Given:

Zinc percentage in a brass = 35%

copper percentage would be - 65% (100 - 35 = 65)

Weight of the brass metal bar = 20.15 ounce

ounces of copper are in the bar = ?

Solution:

The weight of the copper in the brass metal in ounces-

= weight of brass* percentage of copper/100

= 20.15*65/100

= 13.0975 ounces of copper.

2nd method =

The weight of the zinc in the brass metal in ounces-

= weight of brass* percentage of zinc/100

= 20.15*35/100

= 7.0525

The weight of the copper = total weight - weight of zinc

= 13.0975 ounces of copper.

16

explanation:

the marks go by 4s