61.0k views
0 votes
The missing number is a two-digit number that makes a value that is more than 80 but less than 90.

65+

User Shadyar
by
8.1k points

1 Answer

4 votes

The missing number is 25.

Step-by-step explanation:

Let's solve the expression
\(65 + \_\_\)with the condition that the missing number is a two-digit number, and the sum is more than 80 but less than 90.

Let the missing two-digit number be represented by \(xy\), where \(x\) is the tens digit, and y is the units digit.

The given expression is 65 + xy.

We know that the sum should be more than 80 but less than 90, so we have the inequality:


\[80 < 65 + xy < 90\]

Now, substitute 65 + xy back into the inequality:


\[80 < 65 + xy < 90\]


\[80 < 65 + 10x + y < 90\]

Now, solve for x and y using the given conditions.

For the tens digit x:


\[10x\] should be greater than or equal to 15 (to make the sum more than 80).


\[10x \geq 15\]


\[x \geq (15)/(10)\]


\[x \geq 1.5\]

So, x must be 2 (as x is a digit).

For the units digit y:

y should be greater than or equal to 0 (since it's a digit).

So, the missing number is 25, and the expression 65 + 25 equals 90.

Therefore, the detailed solution is that the missing two-digit number is 25.

The probable question can be: If the missing number is a two-digit number that makes a value more than 80 but less than 90 in the expression
\(65 + \_\_\), what is the missing number?

User Janus Troelsen
by
7.7k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.