Home
Class 14
MATHS
Find 150% of x, If x is the least number...

Find `150%` of x, If x is the least number which when divided by 6, 7, 8, 9 and 12 leaves remainders 2, 3, 4, 5 and 8 respectively
A. 750
B.500
C.1000
D.1260

A

B

B

D

C

A

D

C

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we need to find the least number \( x \) that satisfies the given conditions and then calculate \( 150\% \) of that number. ### Step 1: Understand the problem We need to find a number \( x \) such that: - When \( x \) is divided by 6, the remainder is 2. - When \( x \) is divided by 7, the remainder is 3. - When \( x \) is divided by 8, the remainder is 4. - When \( x \) is divided by 9, the remainder is 5. - When \( x \) is divided by 12, the remainder is 8. ### Step 2: Set up the equations From the conditions, we can express \( x \) in terms of the divisors and remainders: - \( x \equiv 2 \mod 6 \) - \( x \equiv 3 \mod 7 \) - \( x \equiv 4 \mod 8 \) - \( x \equiv 5 \mod 9 \) - \( x \equiv 8 \mod 12 \) ### Step 3: Rewrite the equations To simplify, we can rewrite these congruences: - \( x = 6k + 2 \) for some integer \( k \) - \( x = 7m + 3 \) for some integer \( m \) - \( x = 8n + 4 \) for some integer \( n \) - \( x = 9p + 5 \) for some integer \( p \) - \( x = 12q + 8 \) for some integer \( q \) ### Step 4: Adjust the equations To find a common solution, we can adjust each equation to have the same form: - \( x - 2 \equiv 0 \mod 6 \) - \( x - 3 \equiv 0 \mod 7 \) - \( x - 4 \equiv 0 \mod 8 \) - \( x - 5 \equiv 0 \mod 9 \) - \( x - 8 \equiv 0 \mod 12 \) This means we can define a new variable \( y \): - \( y = x - 2 \) Then we have: - \( y \equiv 0 \mod 6 \) - \( y \equiv 1 \mod 7 \) - \( y \equiv 2 \mod 8 \) - \( y \equiv 3 \mod 9 \) - \( y \equiv 6 \mod 12 \) ### Step 5: Find the least common multiple (LCM) Now we need to find the least common multiple of the divisors (6, 7, 8, 9, and 12). Calculating the LCM: - The prime factorization is: - \( 6 = 2 \times 3 \) - \( 7 = 7 \) - \( 8 = 2^3 \) - \( 9 = 3^2 \) - \( 12 = 2^2 \times 3 \) The LCM is obtained by taking the highest power of each prime: - \( LCM = 2^3 \times 3^2 \times 7 = 8 \times 9 \times 7 = 504 \) ### Step 6: Calculate the least number \( x \) Now, since \( y \) must be of the form \( 504k \) for some integer \( k \): - The least value of \( x \) can be found by substituting \( k = 1 \): - \( y = 504 \) - Therefore, \( x = y + 2 = 504 + 2 = 506 \). ### Step 7: Calculate \( 150\% \) of \( x \) Now, we need to calculate \( 150\% \) of \( x \): \[ 150\% \text{ of } 506 = \frac{150}{100} \times 506 = 1.5 \times 506 = 759 \] ### Final Answer Thus, the answer is \( 759 \).
Promotional Banner