Question

A single gram of a certain metallic substance has 0.52 grams of copper and 0.26 grams of zinc. The remaining portion of the substance is nickel. Ben estimated that 0.2 gram of nickel is in 1 gram of the substance. He used this to estimate the amount of nickel in 35 grams of the substance. Find the result of Ben’s estimation strategy. Then, find the exact amount of nickel in 35 grams of the substance.

Answer 1

First of all, if we have 1 gram of a substance that has 0.52 gram of copper and 0.26 gram of zinc, the remainder will be: 

Since we know that the remaining portion of the material is nickel, we have 0.22 gram of metal.

Now, Ben estimates that 1 gram of the substance has 0.2 gram of nickel. To find how many grams of metal are in 35 grams of the material, we are going to multiply the grams of the substance by the gram of nickel:

We can conclude that according to Ben, 35 grams of the content has 7 grams of metal.

But we know that in 1 gram of the substance are not 0.2 gram of nickel but 0.22. So let's multiply the grams of the material by 0.22 to find the actual grams of nickel in it:

We can conclude that 35 grams of the substance have 7.7 grams of metal.