Lily broke a cell sample into 99 batches, each weighing 9, point, 3, times, 10, to the power minus 5 9.3×10

−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 can multiply the weight of each batch by the number of batches.

Given:

  • Weight of each batch = \( 9.3 \times 10^{-5} \) grams
  • Number of batches = 99

Now, we calculate the total weight:

\[ \text{Total weight} = \text{Weight of each batch} \times \text{Number of batches} = 9.3 \times 10^{-5} , \text{grams} \times 99 \]

First, we can multiply \( 9.3 \) by \( 99 \):

\[ 9.3 \times 99 = 920.7 \]

Next, we keep the exponent part the same:

\[ \text{Total weight} = 920.7 \times 10^{-5} , \text{grams} \]

Now, we need to express \( 920.7 \) in scientific notation. We can write \( 920.7 \) as:

\[ 920.7 = 9.207 \times 10^2 \]

Therefore, we can rewrite the total weight as:

\[ \text{Total weight} = 9.207 \times 10^2 \times 10^{-5} \]

Now we combine the powers of ten:

\[ = 9.207 \times 10^{2 - 5} \] \[ = 9.207 \times 10^{-3} , \text{grams} \]

Thus, the weight of the original sample, expressed in scientific notation, is:

\[ \boxed{9.207 \times 10^{-3}} , \text{grams} \]