Find the ratio of the LCM of 44, 10 and 5 to the HCF of 50 and 75.
44 ∶ 5
The problem asks us to find the ratio of two quantities: the Least Common Multiple (LCM) of 44, 10, and 5, and the Highest Common Factor (HCF) of 50 and 75. To solve this, we need to calculate both the LCM and the HCF separately and then find their ratio.
To find the LCM of a set of numbers, we can use the prime factorization method. We find the prime factors of each number and then take the highest power of each unique prime factor.
Now, let's identify all the unique prime factors involved: 2, 5, and 11. We take the highest power of each factor present in any of the numbers:
The LCM is the product of these highest powers:
\(\text{LCM}(44, 10, 5) = 2^2 \times 5^1 \times 11^1 = 4 \times 5 \times 11 = 20 \times 11 = 220\)
So, the LCM of 44, 10, and 5 is 220.
To find the HCF of a set of numbers, we also use the prime factorization method. We find the prime factors of each number and then take the lowest power of each common prime factor.
Now, let's identify the common prime factors. The only common prime factor is 5. We take the lowest power of this common factor:
The HCF is the product of these lowest powers of common factors:
\(\text{HCF}(50, 75) = 5^2 = 25\)
So, the HCF of 50 and 75 is 25.
The question asks for the ratio of the LCM of 44, 10, and 5 to the HCF of 50 and 75. This ratio is LCM : HCF.
Ratio = \(\text{LCM}(44, 10, 5)\) : \(\text{HCF}(50, 75)\)
Ratio = 220 : 25
To express the ratio in its simplest form, we divide both numbers by their greatest common divisor (GCD). We can see that both 220 and 25 are divisible by 5.
The simplified ratio is 44 : 5.
Therefore, the ratio of the LCM of 44, 10, and 5 to the HCF of 50 and 75 is 44 : 5.
| Quantity | Calculation | Value |
|---|---|---|
| LCM(44, 10, 5) | \(2^2 \times 5^1 \times 11^1\) | 220 |
| HCF(50, 75) | \(5^2\) | 25 |
| Ratio (LCM : HCF) | 220 : 25 | 44 : 5 (simplified) |
Understanding LCM and HCF is fundamental for solving problems involving multiples and factors.
| Concept | Definition | Prime Factorization Method | Purpose |
|---|---|---|---|
| LCM (Least Common Multiple) | The smallest positive integer that is a multiple of all the given numbers. | Product of the highest powers of all unique prime factors from the numbers. | Useful in problems involving events that repeat at intervals (e.g., finding when two events happen at the same time again). |
| HCF (Highest Common Factor) or GCD (Greatest Common Divisor) | The largest positive integer that divides all the given numbers without leaving a remainder. | Product of the lowest powers of all common prime factors among the numbers. | Useful in problems involving dividing quantities into equal parts (e.g., finding the largest possible size of equal pieces). |
A ratio is a comparison of two quantities. It can be written as \(a:b\) or \(\frac{a}{b}\). Ratios are often simplified to their lowest terms by dividing both parts by their greatest common divisor.
In this problem, we compared the calculated LCM value with the calculated HCF value by forming a ratio and simplifying it.
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