Difference between 2 no is 4. difference between reciprocal is 4/21. find the nos
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Let the first number be a
Second number = a + 4
According to question,
1/ (a) - 1/ (a+4) = 4/21
=> [ a + 4 - a] / a(a+4) = 4 /21
=> ( 4) / (a^2 + 4a) = 4 /21
=> 84 = 4a^2 + 16a
=> 21 = a^2 + 4a
=> a^2 + 4a - 21 = 0
=> a^2 + 7a - 3a - 21 = 0
=> a ( a + 7) - 3(a + 7) = 0
=> (a+7)(a- 3) = 0
a = 3 and (-7)
Neglecting negative value, we get
a = 3
First number = 3
Second number = 7
Second number = a + 4
According to question,
1/ (a) - 1/ (a+4) = 4/21
=> [ a + 4 - a] / a(a+4) = 4 /21
=> ( 4) / (a^2 + 4a) = 4 /21
=> 84 = 4a^2 + 16a
=> 21 = a^2 + 4a
=> a^2 + 4a - 21 = 0
=> a^2 + 7a - 3a - 21 = 0
=> a ( a + 7) - 3(a + 7) = 0
=> (a+7)(a- 3) = 0
a = 3 and (-7)
Neglecting negative value, we get
a = 3
First number = 3
Second number = 7
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