Question
Download Solution PDFConsider a 2-digit number N. Let P be the product of the digits of the number. If P is added to square of the digit in the tens place of N, we get 84. If P is added to the square of the digit in the unit place of N, we get 60. What is the value of P + N ?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFGiven:
Let the 2-digit number be N = 10×a + b, where:
a = digit in tens place
b = digit in units place
P = a × b
Formula used:
Condition 1: P + a2 = 84
Condition 2: P + b2 = 60
Calculations:
From (1): P = 84 − a2
From (2): P = 60 − b2
⇒ 84 − a2 = 60 − b2
⇒ 24 = a2 − b2
⇒ (a − b)(a + b) = 24
Try factor pairs of 24: (1,24), (2,12), (3,8), (4,6)
Try a − b = 2 and a + b = 12
⇒ Add: 2a = 14 ⇒ a = 7, b = 5
Check P = a × b = 7 × 5 = 35
P + a2 = 35 + 49 = 84
P + b2 = 35 + 25 = 60
N = 10×7 + 5 = 75
P = 35
P + N = 35 + 75 = 110
∴ The correct answer is: 110
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