The LCM of 2^a × 3^2 × 5 and 2^3 × 3^b × 7 is 2^5 × 3^4 × 5 × 7. Find a + b.

9. LCM takes the higher power: (a,3) = 5 gives a = 5; (2,b) = 4 gives b = 4. Sum 9.

The LCM of $2^{a} \times 3^{2} \times 5$ and $2^{3} \times 3^{b} \times 7$ is $2^{5} \times 3^{4} \times 5 \times 7$ . Find $a + b$ .

Competition practiceNumber System, HCF & LCM

LCM takes the higher power:

max (a, 3) = 5

gives

a = 5

;

max (2, b) = 4

gives

b = 4

. Sum 9.

Answer: D) 9

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