Question

1. mary wanted to estimate how many sheets of paper she had left. she knew that each sheet was about 0.1 mm thick. her pack measured 2 cm thick. which is the best estimate of the number of sheets of paper in marys pack? a 50 b 100 c 150 d 200

Explanation:

Step1: Convert units to be consistent

First, convert the thickness of the pack from centimeters to millimeters. We know that \(1\space\text{cm} = 10\space\text{mm}\), so \(2\space\text{cm}=2\times10 = 20\space\text{mm}\).

Step2: Calculate the number of sheets

To find the number of sheets, divide the total thickness of the pack by the thickness of one sheet. The formula is \(\text{Number of sheets}=\frac{\text{Total thickness of pack}}{\text{Thickness of one sheet}}\). Substituting the values, we get \(\frac{20\space\text{mm}}{0.1\space\text{mm per sheet}} = 200\) sheets. Wait, no, wait. Wait, 2 cm is 20 mm, each sheet is 0.1 mm. So number of sheets is \(20\div0.1 = 200\)? Wait, but let's check again. Wait, 0.1 mm per sheet, so 10 sheets would be 1 mm (since \(10\times0.1 = 1\space\text{mm}\)). Then 20 mm (which is 2 cm) would be \(20\times10 = 200\) sheets? Wait, but maybe I made a mistake. Wait, 0.1 mm per sheet, so to get 1 mm, it's 10 sheets. Then 2 cm is 20 mm, so 20 mm divided by 0.1 mm per sheet is \(20\div0.1 = 200\). So the number of sheets is 200.

Answer:

D. 200