Chapter 1, Problem 21RP

a

To determine

To calculate: The angle formed by hands of clock at $1:00$

Answer to Problem 21RP

Angle formed by hands of clock at $1:00$ is $30°$ .

Explanation of Solution

Given information: Here, the time given is $1:00$ .

Formula used: Here, we are using the formula angle formed between any two divisions (i.e., $1$ hour) of clock = $\frac{360°}{12}=30°$ .

Angle formed between $n$ hours = $30°(n)$

Calculation: $\because$ Minute hand is on $12:00$ and hour hand is on $1:00$ .

  $\Rightarrow$ Number of hours from $12:00$ to $1:00$ = $1$ hour

  $\therefore$ Angle formed = $30°\times 1=30°$

b

To determine

To calculate: The angle formed by hands of clock at $11:20$

Answer to Problem 21RP

Angle formed by hands of clock at $11:20$ is $150°$ .

Explanation of Solution

Given information: Here, the time given is $11:20$ .

Formula used: Here, we are using the formula angle formed between any two divisions (i.e., $1$ hour) of clock = $\frac{360°}{12}=30°$ .

Angle formed between $n$ hours = $30°(n)$

Calculation: $\because$ Minute hand is on $04:00$ and hour hand is on $11:00$ .

  $\Rightarrow$ Number of hours from $11:00$ to $04:00$ = $5$ hours

  $\therefore$ Angle formed = $30°\times 5=150°$

c

To determine

To calculate: The angle formed by hands of clock at $04:45$ .

Answer to Problem 21RP

Angle formed by hands of clock at $04:45$ is $210°$ .

Explanation of Solution

Given information: Here, the time given is $04:45$ .

Formula used: Here, we are using the formula of angle formed between any two divisions (i.e., $1$ hour) of clock = $\frac{360°}{12}=30°$ .

Angle formed between $n$ hours = $30°(n)$

Calculation: $\because$ Minute hand is on $09:00$ and hour hand is between $04:00$ .

  $\Rightarrow$ Number of hours from $09:00$ to $04:00$ = $7$ hours

  $\therefore$ Angle formed = $30°\times 7=210°$