Question

I think of a number, double it and my answer is 15

Answer 1

Answer:

I think this is the correct answer

Answer 2

$\huge\bold\red{☆Question☆}$

• I think of a number, double it and my answer is 15.

$\huge\bold\red{♡Solution♡}$

Hey mate! Easily we will use algebraic expression to solve this question.

So according to the sentence any number (X) when doubled (×2) gives the result (=) as (15).

So now let's group the values in the brackets in a sequence.

• $\implies$$\small\bold\red{X×2=15}$

As we know that any constant must be on the R.H.S. (Right hand side) but here 2 (a constant ) is at L.H.S. so it will be moved to R.H.S. by changing it's sign from (×) to (÷).

• $\implies$$\small\bold\red{X=15÷2}$

On division 15 and 2 gives 7.5 as shown below.

$\: \: \: \: 2)15(7.5 \\ - 14 \\ - - - \\ \: \: \: \: \: \: \: 010 \\ \: \: \: \: \: \: - 10 \\ \: \: \: \: \: \: \: - - - \\ \: \: \: \: \: \: \: \: \: \: \: \: \: 000 \\ \: \: \: \: \: \: \: \: - - - -$

• $\implies$$\small\bold\red{X=7.5}$

$\small\rm\red{ANSWER}$=7.5

$\huge\bold\red{Additional \: Information}$

$\text\color{red}{What \: is \: an \: expression?}$

• $\implies$An expression is a combination of constants,variable and mathematical operations.

$\text\color{red}{Constants-}$A fixed value i.e.,any number , such as 1,2,56,100 are all constants because their values are fixed.

$\text\color{red}{Variable-}$- A non-fixed value i.e., any letter such as 'a,b,x,n' , etc are variable.