In a store window, there was a box of berries having a total weight of 200 kg. The berries were 99% water, by weight. After two days in the sun, the water content of the berries was only 90%, by weight. What was the total weight of the berries after two days, in kg?

1 answer

If the berries were 99% water, then 1% of the weight was from non-water content.

Let's call the non-water weight "x."

1% of the weight is x:

0.01(weight) = x

Multiply both sides by 100 to solve for weight:

weight = 100x

If the berries originally weighed 200 kg, then the weight of non-water content was:

weight = 100x = 200 kg

x = 2 kg

So the original 200 kg was made up of 2 kg of non-water content and 198 kg of water.

After two days in the sun, the water content decreased to 90%. Now, 10% of the weight is from non-water content.

Let's call the new weight "w."

10% of the weight is x:

0.1(w) = x

We know that the non-water content stays the same, so:

2 kg = x

Substitute this value of x into the equation for weight:

w = 100x/0.1 = 100(2)/0.1 = 2000 kg

Therefore, the total weight of the berries after two days in the sun was 2000 kg.