Values, Types & Operators Exercises

Problem One

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

• 17 this is a number
• 1 + 2 * 3 + 4 number and the answer is 11
• 800 / 80 / 8 modulo 2
• 400 > 200 true
• 1 !== 1 false
• true || false true
• true && false false
• 20 % 6 2
• 'a' + 'b'ab

Problem Two

What will the following return?

• typeof 4 number
• typeof 'hello' string
• typeof true boolean
• ` Create a truth table for the expression A || B.

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

| A | B | A || B | |-------|-------|--------| | true | true | true | | false | true | true | | true | false | true | | false | false | false |

Problem Four

Create a truth table for the expression !A && !B.

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

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

Problem Five

Create a truth table for the expression !(A || B).

A | B | !(A || B) | |-------|-------|--------| | true | true | false | | false | true | false | | true | false | false | | false | false | 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

            2 + 3 * 2 + 1`.
            2+6+1
            8+1
            9

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+2 4

Problem Eight

Write a step-by-step evaluation for the following expression: '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'`. true && 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'. '123-1'