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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, $$x+y+z = 10+42+60 = 112$$
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