Marcia dissolved 1 kg of salt in 3 litres of water
Bobby dissolved 2 pounds of salt in 7 pints of water
We know that
1 litre = 2.11 pints
We also know that
1 pound = 0.4535 kg
Now if we take the case of Bobby, and convert the pound to
kg then
1 pound = 0.4535 kg
2 pounds = (0.4535 * 2) kg
=
0.907 kg
= 0.91
kg
Bobby dissolved the salt in 7 pints of water
We know
2.11 pints = 1 litre
Then
7 pints = (7/2.11) litre
= 3.32
litres
So we now see that Bobby has dissolved 0.91 kg of salt in
3.32 litres of water
Marcia dissolved 1 kg of salt in 3 litres of water.
So Marcia has made a more concentrated solution since she
has dissolved more salt in less amount of water whereas Bobby has dissolved
less amount of salt in more water.