Many UPTET aspirants face difficulties while preparing for the Percentage because it requires both conceptual clarity and fast calculation skills. Students often struggle to memorise important percentage-fraction conversions. Calculation mistakes are common while finding percentage increase, decrease, or successive changes.
Moreover, many Arithmetic chapters are directly connected to it. Concepts such as profit and loss, discounts, simple interest, compound interest, mark calculation, ratio and proportion, data interpretation, and bundle or quantity-based questions are largely derived from percentage calculations. In many questions, students first need to convert fractions, decimals, or ratios into percentages before applying formulas.
Thus, this is a very important fundamental topic. Read further to understand its basics, the percentage-fraction table, and problem-solving methods.
Percentage is a mathematical concept derived from per and cent (100). It signifies considering everything out of 100. The percentage symbol (%) represents 1/100. For example, 40% means 40/100, or 40 parts out of 100.
These shortcuts are essential for quick calculations:
10%: Means 1/10. To find 10% of a number, divide the number by 10.
Example: 10% of 540 is 54 (540 / 10).
Example: 10% of 600 is 60 (600 / 10).
1%: Means 1/100. To find 1% of a number, divide the number by 100.
Decimal Shift: Dividing by 100 means shifting the decimal point two places to the left.
Example: 1% of 540 is 5.4 (540 / 100).
Example: 1% of 600 is 6 (600 / 100).
Percentage questions in UPTET Maths can often be solved using multiple approaches, depending on the complexity of the problem and the student’s calculation speed. Learning different problem-solving methods helps candidates choose the fastest and most accurate approach during the exam.
Techniques such as the Unitary Method, Conceptual or Mental Math Method, and Direct Ratio Method improve calculation efficiency and reduce dependence on lengthy formulas.
This problem type involves finding Y% of a number when X% of the same number is known.
Method 1: Unitary Method
If 200% = 90
then 1% = 90 / 200.
To find 50%, calculate (90 / 200) * 50 = 22.5.
Method 2: Conceptual/Mental Math
If 200% = 90
then 100% = 90 / 2 = 45 (as 100% is half of 200%).
Then, 50% = 45 / 2 = 22.5 (as 50% is half of 100%).
Method 3: Direct Ratio Method
Formula: To find (Required Percentage) when (Given Percentage) and its (Value) are known: (Required Percentage / Given Percentage) * Value.
Example 1: What is 50% if 350% = 70? (50 / 350) * 70 = (1/7) * 70 = 10.
Example 2: What is 200% if 150% = 60? (200 / 150) * 60 = (4/3) * 60 = 80.
Example 3: What is 45% if 90% = 184? Here, 45% is half of 90%. So, 45% = 184 / 2 = 92.
This type of problem asks you to find the original number (100%) when a percentage difference is given as a specific value.
Method:
Calculate the percentage difference.
Equate this percentage difference to the given value.
Use the unitary method to find 1%, then multiply by 100 for 100%.
Example 1: 32% of a number is 28 more than 27% of the same number. Find the number.
Percentage difference: 32% - 27% = 5%.
Equate: 5% = 28.
Find 1%: 1% = 28 / 5.
Find 100%: 100% = (28 / 5) * 100 = 28 * 20 = 560.
Example 2: 20% of a number is 48 more than 12% of the same number. Find the number.
Percentage difference: 20% - 12% = 8%.
Equate: 8% = 48.
Find 1%: 1% = 48 / 8 = 6.
Find 100%: 100% = 6 * 100 = 600.
Understanding the relationship between fractions and percentages is an important part of Percentage preparation for UPTET Maths. Many exam questions require students to convert fractions to percentages to solve problems quickly.
Since percentages are simply fractions expressed out of 100, learning these conversions helps you perform faster calculations and improves problem-solving accuracy
Efficient Method: Convert percentages to their equivalent simple fractions.
Example: Calculate 16.66% of 720 + 87.5% of 40.
Convert: 16.66% = 1/6 and 87.5% = 7/8.
Calculate: (1/6) * 720 + (7/8) * 40 = 120 + 35 = 155.
To convert a fraction to a percentage, multiply by 100.
1 = 100%.
|
Category |
Fraction |
Percentage |
Memory Trick |
|
Basic Conversions (Exact Values) |
1/2 |
50% |
Half of 100 |
|
1/4 |
25% |
Quarter of 100 |
|
|
3/4 |
75% |
25% × 3 |
|
|
1/5 |
20% |
Divide 100 by 5 |
|
|
2/5 |
40% |
Double of 20% |
|
|
3/5 |
60% |
Triple of 20% |
|
|
4/5 |
80% |
Four times 20% |
|
|
1/10 |
10% |
Decimal shift trick |
|
|
Repeating Decimal Conversions |
1/3 |
33.33% |
Repeating “33” indicates 1/3 |
|
2/3 |
66.66% |
Double of 33.33% |
|
|
1/6 Based Conversions |
1/6 |
16.66% / 16.67% |
Important value to memorize |
|
5/6 |
83.33% |
100% − 16.67% |
|
|
1/7 Based Conversions |
1/7 |
14.28% |
Use 14 times table |
|
2/7 |
28.56% |
14 × 2 = 28 |
|
|
3/7 |
42.84% |
14 × 3 = 42 |
|
|
4/7 |
57.12% |
Continue pattern |
|
|
5/7 |
71.40% |
Continue pattern |
|
|
1/8 Based Conversions |
1/8 |
12.5% |
Half of 1/4 = 25% |
|
3/8 |
37.5% |
12.5 × 3 |
|
|
5/8 |
62.5% |
12.5 × 5 |
|
|
7/8 |
87.5% |
12.5 × 7 |
|
|
1/9 Based Conversions |
1/9 |
11.11% |
Use 11 times table |
|
2/9 |
22.22% |
Double of 11.11% |
|
|
4/9 |
44.44% |
11 × 4 pattern |
|
|
1/11 Based Conversions |
1/11 |
9.09% |
Use 9 times table |
|
2/11 |
18.18% |
Double of 9.09% |
|
|
3/11 |
27.27% |
9 × 3 pattern |
The key principle for advanced problems is to convert decimal percentages to their equivalent fractions first.
Example 1: What is 62.5% of a number if 37.5% of the number is 240?
Convert Percentages to Fractions:
37.5% = 3/8 (since 37.5 / 12.5 = 3)
62.5% = 5/8 (since 62.5 / 12.5 = 5)
Solve using Fractions:
Given: 3/8 = 240.
Find 1/8: 1/8 = 240 / 3 = 80.
Find 5/8: 5/8 = 5 * 80 = 400.
Example 2: What is 36.36% of a number if 44.44% of the number is 132?
Convert Percentages to Fractions:
44.44% = 4/9 (related to 1/9 where 11 times table applies, 11 * 4 = 44)
36.36% = 4/11 (related to 1/11 where 9 times table applies, 9 * 4 = 36)
Solve using Fractions:
Given: 4/9 = 132.
The full number (1) would be (132 * 9) / 4.
To find 36.36% (which is 4/11) of this number: ((132 * 9) / 4) * (4 / 11) = (132 * 9) / 11 = 12 * 9 = 108.
Percentages form the foundation of many important topics in UPTET Maths, including profit and loss, discounts, marks calculation, ratio-based questions, and data interpretation.
A clear understanding of fraction-to-percentage conversions, shortcut tricks, and different problem-solving methods helps candidates improve speed, accuracy, and confidence during the exam.
Regular practice of important percentage concepts and mental calculation techniques can reduce common mistakes and strengthen overall arithmetic preparation for UPTET.
