Answer: It's 72.
Step-by-step explanation: They deleted my answer <:(
Where’s the picture? Or link?
Answer:
7 students play an instrument.
Calculation:
35=100%
20%=[20×35]÷100
=7
Answer:
Density is defined as:
Density = mass/volume.
We know that:
For liquid A:
Density = 70kg/m^3
Mass = 1400kg
Then the volume is:
Volume = mass/density = (1400kg)/(70kg/m^3) = 20 m^3
For liquid B:
Density = 280 kg/m^3
Volume = 30m^3
We can find the mass of liquid B as:
mass = density*volume = (280kg/m^3)*(30m^3) = 8400 kg
We know that liquid C is a mixture of liquid A and B.
Then the mass of liquid C will be equal to the sum of the masses of liquid A and B, then:
Mass of liquid C = 1400kg + 8400kg = 9800kg
The same happens for the volume, then:
Volume of liquid C = 30m^3 + 20m^3 = 50m^3
Then the density of liquid C is:
Density of liquid C = (9800kg)/(50m^3) = 196 kg/m^3