Answers

2014-10-05T11:19:19+05:30
Let the two numbers be A and B
=>A+B=15                      .............(1)
and
1/A +1/B=3/10
⇒(A+B)/AB = 3/10
from (1)
(A+B)/AB = 15/AB
⇒15/AB = 3/10
⇒AB = 50        ............(2)
solving (1) and (2)
A = 10 and B = 5
or
A = 5 and B = 10

2 4 2
2014-10-05T11:33:19+05:30
Let the two numbers are X and y
X+Y=15.....................(1)
SUMOF RECIPROCAL OF THAT TWO NUMBER=>1/X+1/Y=3/10
=>X+Y/XY = 3/10
=>X+Y = 3XY/10...........................(2)
SUBSTITUTE X+Y VALUE  IN (2)
=>15*10 = 3XY
=>150 = 3XY
=>50=XY
=>Y=50/X..........................(3)
(3) IN (1)
X+50/X=15
X²+50=15X
X²-15X+50=0
X²-5X-10X+50=0
X(X-5)-10(X-5)=0
(X-10)(X-5)=0
X=10 AND X=5
SUBSTITUTE X VALUE IN (1)
10+Y=15 AND 5+Y=15
Y=5 AND Y=10



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