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How? It could be c or d

Related Question

The product of two 2-digit numbers is 4424. If the product of their unit digits is 54 and the product of their ten's digits is 35, the two numbers are
a. 67, 95 b. 57, 69
c. 59, 76 d. 56, 79

Answer

There are two ways to go into this problem. 

a. Finding all the two digit factors of 4424, and the checking the conditions for them.

b. Cross checking the conditions for the given options. 

Let us see the factors of 4424: 

4424 = 2 * 2 * 2 * 7 * 79

We can see that it can have a maximum of 2 two-digit factors, one of which is 79 and the other one is 2 * 2 * 2 * 7 = 56.

Let us now check the given conditions for 56 and 79.

1. The product of tens digits = 5 * 7 = 35 - Matching.

2. The product of units digits: 6 * 9 = 54 - Matching. 

 

Hence, 56 and 79 is the right answer.

Both c and d are correct.

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