Question Number 179140 by Shrinava last updated on 25/Oct/22

(1/(3a)) = (1/(4b)) = (1/(6c))   and   a+b+c=27  find   a−c=?

Answered by Frix last updated on 25/Oct/22

a=4t  b=3t  c=2t  a+b+c=27  9t=27  t=3  a=12  b=9  c=6  a−c=6

Commented byRasheed.Sindhi last updated on 25/Oct/22

Typo sir:    a+b+c=27⇒9t=27

Commented byFrix last updated on 25/Oct/22

yes thank you

Answered by Rasheed.Sindhi last updated on 25/Oct/22

3a=4b=6c ∧ a+b+c=27; a−c=?  [ _(  _( ) ) 3a=6c⇒a−2c=0⇒a−c=c_(Hence   we need   value of  c)   ]  ▶Eleminating b from a+b+c=27  3a=4b=6c⇒ { ((b=(3/2)c)),((b=(3/4)a)) :}   •a+b+c=27⇒a+(3/4)a+c=27                              ⇒7a+4c=108....(i)  •a+b+c=27⇒a+(3/2)c+c=27                               ⇒2a+5c=54....(ii)  ▶Eleminating a from (i) & (ii)   { ((2×(i)⇒14a+8c=216)),((7×(ii)⇒14a+35c=378)) :}⇒27c=162                ⇒c=((162)/(27))=6  •3a=6c⇒a−2c=0⇒a−c=c=6

Answered by som(math1967) last updated on 25/Oct/22

(1/(3a))=(1/(4b))=(1/(6c))  3a=4b=6c  ((3a)/(12))=((4b)/(12))=((6c)/(12))  (a/4)=(b/3)=(c/2)=k (let)  ∴a=4k, b=3k,c=2k  a+b+c=27  ⇒4k+3k+2k=27  ⇒9k=27⇒k=3   a−c=4k−2k=2k=2×3=6

Answered by Rasheed.Sindhi last updated on 25/Oct/22

(1/(3a)) = (1/(4b)) = (1/(6c))  ∧ a+b+c=27; a−c=?  (1/(3a)) = (1/(4b)) = (1/(6c))⇒((4×1)/(4(3a))) = ((3×1)/(3(4b))) = ((2×1)/(2(6c)))              =(9/(12(a+b+c)))=(3/(4×27))=(1/(36))        3a=36 ∧ 6c=36        3a=36 ∧ 3c=18        ⇒3a−3c=18        ⇒a−c=6