Sign in
Please select an account to continue using cracku.in
↓ →
If $$12^{12x}\times 4^{24x+12}\times 5^{2y}=8^{4z}\times 20 ^{12x} \times 243^{3x-6}$$, where x , y and z are
natural numbers, then $$ x + y + z $$ equals
Correct Answer: 112
$$12^{12x}\times 4^{24x+12}\times 5^{2y}=8^{4z}\times 20 ^{12x} \times 243^{3x-6}$$
On rewriting after prime factorisation, we get,
$$\cancel{2^{24x}}\times 3^{12x} \times 2^{48x+24}\times 5^{2y} = 2^{12z}\times \cancel{2^{24x}} \times 5^{12x} \times 3^{15x-30}$$
Since LHS = RHS, the corresponding powers must be equal. We have,
Powers of $$3$$: $$12x = 15x-30$$ or $$x=10$$, and
Powers of $$2$$: $$48x+24 = 12z$$ or $$4x+2 = z$$ or $$z = 42$$
Powers of $$5$$: $$2y = 12x$$ or $$y= 6x$$ or $$y=60$$
Therefore, $$x+y+z = 10+42+60 = 112$$
Click on the Email ☝️ to Watch the Video Solution
Create a FREE account and get:
Book Free CAT Mentorship
Get personalized CAT strategy from a 99%iler
500+ students mentored
OTP Verification
Enter the 6-digit code sent to your phone
Booking Summary
Enter OTP
Didn't receive the OTP?
Start your IIM journey with the right preparation and crack CAT 2026.
Educational materials for CAT preparation