Which number of the following is not equal to 2.4?

Options

A. `2(2)/(5)`
B. `22.5%`
C. `(12)/(5)`
D. `2(4)/(10)`

Answer

To determine which number is not equal to 2.4, we will evaluate each option provided. Let's go through the options step by step.

### Step 1: Analyze Option 1
**Option 1: 2 (2/5)**
This is a mixed fraction. To convert it into a proper fraction, we multiply the whole number (2) by the denominator (5) and add the numerator (2).

\[ 2 \times 5 + 2 = 10 + 2 = 12 \]

So, we have:

\[ \text{Mixed fraction} = \frac{12}{5} \]

Now, divide 12 by 5:

\[ 12 \div 5 = 2.4 \]

**Conclusion:** Option 1 is equal to 2.4.

### Step 2: Analyze Option 2
**Option 2: 22.5%**
To convert a percentage to a decimal, we divide by 100:

\[ 22.5\% = \frac{22.5}{100} = 0.225 \]

**Conclusion:** Option 2 is not equal to 2.4.

### Step 3: Analyze Option 3
**Option 3: 12.5**
This is already in decimal form.

**Conclusion:** Option 3 is not equal to 2.4.

### Step 4: Analyze Option 4
**Option 4: 2 (2/10)**
This is also a mixed fraction. Convert it into a proper fraction:

\[ 2 \times 10 + 2 = 20 + 2 = 22 \]

So, we have:

\[ \text{Mixed fraction} = \frac{22}{10} = 2.2 \]

**Conclusion:** Option 4 is not equal to 2.4.

### Final Conclusion
After analyzing all options, we find that **Option 2 (22.5%)** is the only one that is not equal to 2.4.

---