Respuesta :

Given: 
M1 = 6.5 kg of books
M2 = 1.5 kg of CDs
M3 = 2.0 kg of DVDs

Required: percent by mass of each object

Solution:
First, we calculate the total mass.

M = 6.5 kg + 1.5 kg + 2.0 kg =  10 kg

Percent by mass is calculated by getting the ration of the mass of an object and the total mass multiplied by 100 to get the percent.

%M1 = 6.5 / 10 x 100 = 65%
%M2 = 1.5/10 x 100 = 15%
%M3 = 2.0/10 x 100 = 20%

%M1 = 6.5 / 10 x 100 = 65%

%M2 = 1.5/10 x 100 = 15%

%M3 = 2.0/10 x 100 = 20%