Holooly Plus Logo
Holooly Plus Logo

Question 1.13: A child is 21.5 inches long at birth. How long is this in ce...

A child is 21.5 inches long at birth. How long is this in centimeters?
ANALYSIS This problem calls for converting from inches to centimeters, so we will need to know how many centimeters are in an inch and how to use this information as a conversion factor.

BALLPARK ESTIMATE It takes about 2.5 cm to make 1 in.,  and so it should take two and a half times as many centimeters to make a distance equal to approximately 20 in., or about 20 in.    \times  2.5 = 50 cm.

The blue check mark means that this solution has been answered and checked by an expert. This guarantees that the final answer is accurate.
Learn more on how we answer questions.
\begin{aligned}\begin{matrix}\text{STEP 1: Identify given information.}\\\text{STEP 2: Identify answer and units.}\\\text{STEP 3: Identify conversion factor.}\\\text{STEP 4: Solve. Multiply the known length (in inches) by the}\\ \text{conversion factor so that units cancel, providing the answer}\\ \text{(in centimeters)}\end{matrix}&\left|\begin{matrix}Length = 21.5 in.\\ Length = ?? cm 1 \\ 1 in. = 2.54 cm \rightarrow  \frac {2.54 cm}{1 in.}\\ 21.5 \cancel { in}. \times \frac {2.54 cm}{ 1 \cancel{ in}.} = 54.6 cm \text{(Rounded off from 54.61)}\end{matrix}\right.\end{aligned}

BALLPARK CHECK How does this value compare with the ballpark estimate we made at the beginning? Are the final units correct? 54.6 cm is close to our original estimate of 50 cm.

Related Answered Questions

Question: 1.17

Taking a bath might use about 95 kg of water. How much energy (in calories and Joules) is ...

Verified Answer:

ANALYSiS From the amount of water being heated (95...
Question: 1.8

A clinical laboratory found that a blood sample contained 0.0026 g of phosphorus and 0.000 101 g of iron. (a) Give these quantities in scientific notation. (b) Give these quantities in the units normally used to report them—milligrams for phosphorus and micrograms for iron. ...

Verified Answer:

(b) We know from Table 1.6 that  1  mg = 1...
Question: 1.18

What volume of isopropanol (rubbing alcohol) would you use if you needed 25.0 g? The density of isopropanol is 0.7855 g /mL at 20 °C. AnAlySiS The known information is the mass of isopropanol needed (25.0 g). The density (0.7855 g/mL) acts as a conversion factor between mass and the unknown ...

Verified Answer:

STEP 1: Identify known information. Mass of rubbin...
Question: 1.16

A body temperature above 107 °F can be fatal. What does 107 °F correspond to on the Celsius scale? ANALYSIS Using the temperature (in °F) and the appropriate temperature conversion equation, we can convert from the Fahrenheit scale to the Celsius scale. ...

Verified Answer:

STEP 1: Identify known information. Temperature = ...
Question: 1.15

Administration of digitalis to control atrial fibrillation in heart patients must be carefully regulated because even a modest overdose can be fatal. To take differences between patients into account, dosages are sometimes prescribed in micrograms per kilogram of body weight (mg/kg). Thus, two ...

Verified Answer:

STEP 1: Identify known information. Patient weight...
Question: 1.14

A patient requires an injection of 0.012 g of a pain killer available as a 15 mg /mL solution. How many milliliters of solution should be administered? ...

Verified Answer:

STEP 1: Identify known information. Dosage = 0.012...
Question: 1.5

How many significant figures do the following measurements have? (a) 2730.78 m (b) 0.0076 mL (c) 3400 kg (d) 3400.0 m² ANALYSIS All nonzero numbers are significant; the number of significant figures will then depend on the status of the zeroes in each case. (Hint: Which rule applies in each case?) ...

Verified Answer:

(a) Six (rule 1; Zeroes in the middle of a number ...
Question: 1.6

There are 1,760,000,000,000,000,000,000 molecules of sucrose (table sugar) in 1 g. Use scientific notation to express this number with four significant figures. ...

Verified Answer:

The first four digits—1, 7, 6, and 0—are significa...
Question: 1.4

The HIV-1 virus particles seen in the margin photo on p. 48 are very small, on the order of 0.000 000 120 m in diameter. Express this value using scientific notation and using an appropriate numerical prefix to modify the basic unit. ...

Verified Answer:

To convert to scientific notation we have to move ...
Question: 1.12

(a) Convert 0.75 lb to grams. (b) Convert 0.50 qt to deciliters. ANALYSIS Start with conversion factors and set up equations so that units cancel appropriately. ...

Verified Answer:

(a) Select the conversion factor from Worked Examp...