Question

(Math Plato)

Twenty-seven minus of a number (x) is not more than 36. What is the number? A. x > 42 B. x ≥ -6 C. x < 3 D. x ≤ -6

Answer 1

None of them

`x\geq -9`

Explanation:

`27` minus a number
`x` is not more than
`36` translates algebraically to

`27-x\leq 36`

(Not more than
`36` means either
`36` or less than
`36` that's why we have used equal or less than inequality)

`27-x\leq 36`

Subtract 27 from both sides

`-27+27-x\leq 36-27`

`-x\leq 9`

Multiply both sides by -1

Multiplying by -1 will reverse the inequity

`x\geq -9`

Hence values of
`x` equal or greater than
`-9` will satisfy the inequality

Verification:

Lets take
`x=-4`

`27-x\leq 36`

`27-(-4)\leq 36`

`27+4\leq 36`

`31\leq 36` (satisfied)

Lets take
`x=2`

`27-x\leq 36`

`27-(2)\leq 36`

`25\leq 36` (satisfied)