Numbers

Question 1

What is one of the most common datatypes in JavaScript?

Answer 1

Strings

Question 2

What are booleans?

Answer 2

True or false outcomes are booleans.

Question 3

Can JavaScript numbers do simple and complex math?

Answer 3

Yes

It is possible to do simple + complex math with JS numbers.

Question 4

How is math used in practical ways online?

Answer 4

Total Cost in online stores

Adding points in online games

Keeping track of metrics in web apps

Question 5

What role do random numbers play?

Answer 5

Random numbers add variety and surprise to games.

Question 6

Can numbers be positive or negative in JavaScript numbers?

Answer 6

Yes

Question 7

Can you use decimals or only whole integers?

Answer 7

Both whole integers and decimals

Question 8

How do you assign numbers?

Answer 8

You can store numbers in variables by using the equal sign.

Question 9

Do numbers need special characters?

Answer 9

No, you don’t need quote marks.

If you add quote marks, it’s a string, not a number.

Question 10

Can you use commas for longer numbers?

Ex: 1,456,789

Answer 10

No

You cannot use commas

Commas produces errors

Question 11

What is the arithmetic operator for addition?

Answer 11

+

Question 12

What is the arithmetic operator for subtraction?

Answer 12

-

Question 13

What is the arithmetic operator for multiplication?

Answer 13

*

Question 14

What is the arithmetic operator for division?

Answer 14

/

Question 15

Can you combine variables with numbers as part of JavaScript arithmetic?

Answer 15

Yes

You can add variables with numbers.

Example: game scores

Question 16

How do you write this in shorthand version?

score = score + 10;

Answer 16

Shorthand version of arithmetic simplifies
it by not having to write the variable name twice.

score += 10;

Question 17

How do you flip the order of the signs in the shorthand version?

Answer 17

Put the operator before equal sign

+=

-=

*=

/=

Question 18

For subtraction shorthand, how would you simplify the following code?

Answer 18

score -= 20;

Question 19

For multiplication, how do you simplify it in shorthand?

Answer 19

Question 20

For division, what’s the shorthand version?

Answer 20

Question 21

To create a math program, you should start by

Answer 21

creating your variables and assigning values

Question 22

Once you have your variables, how do you make your formula?

Answer 22

The formula itself goes into a new variable.

In this example, variables are multiplied by variables.

The solution is assigned to a new variable.

Question 23

In this sales total example, what does it calculate?

Answer 23

The sales total is equal to quantity * retailPrice.

Question 24

How would the profit be calculated using a new variable named const profit?

Answer 24

Question 25

What happens if you treat numbers as strings?

Answer 25

The numbers are laid out next to each other, rather than following arithmetic rules. Example 5+ 4 becomes 54, rather than 9.

Question 26

What property helps you convert strings into numbers?

Answer 26

ParseInt()

Question 27

What does ParseInt() do?

Answer 27

ParseInt() converts strings into integers

Question 28

Can ParseInt() take positive/negative numbers?

Answer 28

Yes

Question 29

Can you use decimals with ParseInt()?

Answer 29

No, whole numbers only can be used with ParseInt()

Question 30

In what variable is ParseInt() used in this program?

Answer 30

const totalBadges

Question 31

Why is ParseInt() useful?

Question 32

What is a floating point number?

Answer 32

It's a decimal number. 3.14

Question 33

What does parseFloat() do?

Answer 33

It accepts decimal numbers for math formulas.

Question 34

What does NaN stand for?

Answer 34

**Not a number** It's an error message

Question 35

What are primative data types? N.B.S.

Answer 35

**N.B.S.** Numbers Booleans Strings

Question 36

What does math.round do?

Answer 36

It rounds up to the next whole integer.

Question 37

What result would this produce?

Answer 37

It would round to 2.

Question 38

What number would this math.round example round to?

Answer 38

45

Question 39

What are 2 reasons why would you want to generate a random number?

Answer 39

Variety Surprise Random image Random question

Question 40

What property do you use to create random numbers?

Answer 40

**Math.random**

Question 41

What does Math.floor do?

Answer 41

Math.floor rounds decimals down.

Question 42

What does Math.ceil do?

Answer 42

Mail.ceil rounds decimals down.

Question 43

For math.round, what logic does it use to round up or down?

Answer 43

If it is above .5, Math.round, rounds up. If it is .4 or below, Math.round, rounds down.

Question 44

Whats the lowest number that would be returned from this Math.random example?

Answer 44

1

Question 45

What is the highest number it would return?

Answer 45

6

Question 46

What range would this Math.random stay within?

Answer 46

1 and 6 It returns a value between 1 and 6.

Question 47

When dealing with parenthesis, which runs first, inner or outer?

Answer 47

inner parenthesis runs first

Question 48

Does Math.random() return whole numbers or decimals?

Answer 48

Typically it returns decimals Even when multiplied against integers

Question 49

Using const inputHigh, collect input from the user. Collect the number using prompt method Store the prompt in a variable

Answer 49

Question 50

Use ParseInt to convert the input to a number Using inputHigh to store highest number possible Variable is constant Variable name is highNumber

Answer 50

const highNumber = parseInt(inputHigh);

Question 51

Use Math.random() and the user's number to generate a random number const is randomNumber Math.floor to round down use + 1 for a wider range

Answer 51

Question 52

Create a message displaying the random number Use console.log Use string interpolation ${} Use text for user Use the range between 1 and high number

Answer 52

Question 53

Check that the user provides a number using a conditional statement, highNumber variable, Math.floor, + 1. With 2 console.logs for the random number range and message to user.

Answer 53

Question 54

How do you ask for a random number between two numbers? Use const inputLow and inputHigh with prompts Use the parseInt for both low and high number Generate a random number with Math.floor Create a formula with const randomNumber Conditional statement Print out to console.log the random number Console.log to provide a two numbers, if needed

Answer 54