*Estimating Percents Summary** To estimate $$ 10 \% $$. $$ \qquad $$ Mole decimal one spot left $$ 10 \%-7.5 $$ To estimate any multiple of $$ 10 \% $$ esimate $$ 10 \% $$ and multiply $$ 10 \%-3 / 2 $$ Example: to estimate $$ 30 \% $$. $$ 10 \% imes 3 $$ $$ \qquad $$ $$ 10 \% \div 2 $$ To estimate $$ 5 \% $$ - $$ \qquad $$ 1. To estimate $$ 50 \% $$. cut in hale cut in hasp twice To estimate $$ 25 \% $$ $$ \qquad $$ Toestimate $$ 1 \% $$-Move decimal left 2 Spots $$ \qquad $$ To estimate \% you will pay - $$ \qquad $$ Subtract $$ 100 \% $$-discount \%

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*Estimating Percents Summary** To estimate $$ 10 \% $$. $$ \qquad $$ Mole decimal one spot left $$ 10 \%-7.5 $$ To estimate any multiple of $$ 10 \% $$ esimate $$ 10 \% $$ and multiply $$ 10 \%-3 / 2 $$ Example: to estimate $$ 30 \% $$. $$ 10 \% 	imes 3 $$ $$ \qquad $$ $$ 10 \% \div 2 $$ To estimate $$ 5 \% $$ - $$ \qquad $$ 1. To estimate $$ 50 \% $$. cut in hale cut in hasp twice To estimate $$ 25 \% $$ $$ \qquad $$ Toestimate $$ 1 \% $$-Move decimal left 2 Spots $$ \qquad $$ To estimate \% you will pay - $$ \qquad $$ Subtract $$ 100 \% $$-discount \%

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**Estimating Percents Summary**

Estimating percentages is a valuable skill for quick calculations, especially when you need a rough figure without precise computation. Below is a summary of techniques to estimate various common percentages:

1. **Estimating 1%**
   - **Method:** Move the decimal point two places to the left.
   - **Example:**  
     - 1% of 250 = 250 → 2.50 → **\$2.50**

2. **Estimating 5%**
   - **Method:** Take half of 10%.
   - **Steps:**
     1. Estimate 10% by moving the decimal one place to the left.
     2. Divide that number by 2.
   - **Example:**  
     - 10% of 200 = 20  
     - 5% ≈ 20 ÷ 2 = **\$10**

3. **Estimating 10%**
   - **Method:** Move the decimal point one place to the left.
   - **Example:**  
     - 10% of 350 = **\$35**

4. **Estimating 15%**
   - **Method:** Combine 10% and 5%.
   - **Steps:**
     1. Calculate 10%.
     2. Add half of 10% (which is 5%).
   - **Example:**  
     - 10% of 400 = 40  
     - 5% ≈ 40 ÷ 2 = 20  
     - 15% ≈ 40 + 20 = **\$60**

5. **Estimating Multiples of 10% (e.g., 20%, 30%, etc.)**
   - **Method:** Calculate 10% and multiply by the desired factor.
   - **Example:**  
     - 10% of 150 = 15  
     - 30% ≈ 15 × 3 = **\$45**

6. **Estimating 25%**
   - **Method:** Take half of 50%.
   - **Steps:**
     1. Calculate 50% (half of the total).
     2. Divide that number by 2.
   - **Example:**  
     - 50% of 80 = 40  
     - 25% ≈ 40 ÷ 2 = **\$20**

7. **Estimating 50%**
   - **Method:** Simply take half of the total amount.
   - **Example:**  
     - 50% of 120 = **\$60**

8. **Estimating 100% minus Discount Percentage (To Find the Percentage You'll Pay)**
   - **Method:** Subtract the discount percentage from 100%.
   - **Example:**  
     - If there's a 20% discount, you'll pay 80% of the original price.

**Additional Tips:**
- **Combining Estimates:** For percentages that are not straightforward (e.g., 18%), break them down into known percentages (10% + 5% + 3%) and estimate each part separately.
- **Practice with Real Numbers:** Apply these methods to everyday calculations, such as discounts, tips, taxes, and interest rates, to become more comfortable with quick estimations.

**Example Application:**

*Calculate 25% of \$200*

1. **50% of \$200:**  
   \$200 ÷ 2 = **\$100**

2. **25% is half of 50%:**  
   \$100 ÷ 2 = **\$50**

*Therefore, 25% of \$200 is approximately \$50.*

By mastering these estimation techniques, you can perform quick and effective percentage calculations without the need for a calculator.
**Estimating Percents Summary** - **1%:** Move the decimal two places left. - Example: 1% of 250 = \$2.50 - **5%:** Take half of 10%. - Example: 10% of 200 = \$20 → 5% ≈ \$10 - **10%:** Move the decimal one place left. - Example: 10% of 350 = \$35 - **15%:** Add 10% and 5%. - Example: 10% of 400 = \$40 → 5% ≈ \$20 → 15% ≈ \$60 - **Multiples of 10% (e.g., 20%, 30%):** Calculate 10% and multiply by the factor. - Example: 10% of 150 = \$15 → 30% ≈ \$45 - **25%:** Take half of 50%. - Example: 50% of 80 = \$40 → 25% ≈ \$20 - **50%:** Half of the total amount. - Example: 50% of 120 = \$60 - **Percentage You'll Pay:** Subtract the discount from 100%. - Example: 20% discount → 80% of the original price **Additional Tips:** - Break down complex percentages into known parts. - Practice with real numbers for better understanding. **Example:** - 25% of \$200 ≈ \$50

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