Values, Types & Operators Exercises

Problem One

What are the types of the following expressions and what do they evaluate to, and why?

• 17 number
• 1 + 2 * 3 + 4 number = 11 -> 1+6+4 -> 7+4 -> 11
• 800 / 80 / 8 number = 1.25 -> 800/80 -> 10/8 -> 1.25
• 400 > 200 boolean = true 400 is greater than 200
• 1 !== 1 logic operator = false
• true || false logic operator = true
• true && false logic operator = false
• 20 % 6 remainder operator
• 'a' + 'b' string ab

Problem Two

What will the following return?

• typeof 4 number
• typeof 'hello' string
• typeof true boolean
• 2 === 1 || 3 === 4 false

Problem Three

Create a truth table for the expression A || B. | A | B | A || B | |-------|-------|--------| | true | true | true | | false | true | true | | true | false | true | | false | false | false |

For reference, here is a truth table for the expression A && B:

A	B	A && B
true	true	true
false	true	false
true	false	false
false	false	false

Problem Four

Create a truth table for the expression !A && !B. | A | B | !B | !A | !A && !B | |-------|-------|--------|--------| | true | true | false | false | false |
| false | true | false | true | false |
| true | false | true | false | false |
| false | false | true | true | true | For reference, here is a truth table for the expression A && !B:

A	B	!B	A && B
true	true	false	false
false	true	false	false
true	false	true	true
false	false	true	false

Problem Five

Create a truth table for the expression !(A || B)| A | B | !B | !A | !(A || B) | |-------|-------|--------|--------| | true | true | false | false | false |
| false | true | false | true | true |
| true | false | true | false | true |
| false | false | true | true | true |

Problem Six

Write a step-by-step evaluation for the following expression (remember order of operations): 2 + 3 * 2 + 1. For reference, here is a exp of a step-by-step evaluation:

1 + 2 + 3 + 4  
    3 + 3 + 4
        6 + 4
            10

Problem Seven

Write a step-by-step evaluation for the following expression (remember order of operations): 4 / 2 + 8 / 4. 4 / 2 + 8 / 4
2 + 8 / 4 2 + 2 4

Problem Eight

Write a step-by-step evaluation for the following expression: 'ca' + 'ter' + 'pi' + 'llar'. 'ca' + 'ter' + 'pi' + 'llar' 'cater' + 'pi' + 'llar' 'caterpi' + 'llar' caterpillar

Problem Nine

Write a step-by-step evaluation for the following expression: 2 * 4 === 8 && 'car' + 'pool' === 'carpool'. 2 * 4 === 8 && 'car' + 'pool' === 'carpool' 8 === 8 && 'car' + 'pool' === 'carpool' 8 === 8 && 'carpool' === 'carpool' true && true true

Problem Ten

Write a step-by-step evaluation for the following expression: '1' + '2' + '3' - '1'. '1' + '2' + '3' - '1' '12' + '3' - '1' '123' -'1' '122'