Lily broke a cell sample into 9 batches, each weighing 9.3 x 10^-5

grams. How much did the original sample weigh? Use scientific notation to express your answer.

1 answer

To find the original weight of the cell sample, we need to multiply the weight of one batch by the number of batches.

Each batch weighs \(9.3 \times 10^{-5}\) grams, and there are 9 batches:

\[ \text{Original weight} = \text{Weight of one batch} \times \text{Number of batches} \]

\[ \text{Original weight} = (9.3 \times 10^{-5} , \text{grams}) \times 9 \]

Now, we can calculate this:

  1. First, multiply the numerical parts:

\[ 9.3 \times 9 = 83.7 \]

  1. Since \(9 = 9.0 \times 10^0\), we maintain the \(10^{-5}\):

\[ \text{Original weight} = 83.7 \times 10^{-5} , \text{grams} \]

  1. We now need to express \(83.7\) in scientific notation. \(83.7\) can be written as \(8.37 \times 10^1\):

\[ \text{Original weight} = (8.37 \times 10^1) \times 10^{-5} \]

  1. When multiplying the powers of ten, we add the exponents:

\[ 10^1 \times 10^{-5} = 10^{1-5} = 10^{-4} \]

  1. Now, combine these together:

\[ \text{Original weight} = 8.37 \times 10^{-4} , \text{grams} \]

Thus, the original sample weighed

\[ \boxed{8.37 \times 10^{-4}} \text{ grams}. \]