If (2.5) ^10=w then w is nearly equal to?
a)5500 b)9500 c)10500 d)5500

• I did it diferently
  x = 2.5^10
  then log x =10log 2.5 =10log(5/2) = 10(log 5 - log 2) =10(0.3980) (Solving with given log values
  log x = 3.98 so x = 10^(3.98)
  We know 10^4 = 10000. Hence x= 10^3.98 will be obviously less than 10000
  so the distance between 9500 to x will be less than 500 and distance between x and 10000 will be >500
  
  Hence 9500 is the ans
• 9 years agoHelpfull: Yes(23) No(3)
• 2.5 ^ 10
  => (5 ^10) /(2^10)
  => 3125*3125/1024
  => here 1024 strikes 3125 nearly 3 times
  => so 3* 3125= 9375
  => so nearly 9500
  ans (b)
• 9 years agoHelpfull: Yes(13) No(0)
• 2.5^10
  =(25/10)^10
  =(25/4)^5
  =6.25^5
  6^5 is7776 and 6.3^5 is 9924 hence 9500 ans
• 9 years agoHelpfull: Yes(1) No(3)
• if, W=(2.5)^10
  take log both sides
  => logW = 10*log(2.5) =10*log(5/2)
  => logW = 10(log5-log2)= 10*0.398 =3.98
  => W = 10^(3.98)
  => W = 9549 (approx) i.e near to 9500
• 9 years agoHelpfull: Yes(1) No(0)
• ABHISHEK SANWAL:: I suggest to just remember the values of log2, log5, log3 log7 because it reduces our calculation time.
  
  log 2 is 0.3010
  log 3 0.4771
  log 5 0.6990
  log 7 0.85
  
  SO incase if u want to find log 6 u can do it as log 2 + log 3 and put an approximate value.
• 8 years agoHelpfull: Yes(1) No(0)
• how ti find the values of log 5 nd log 2 ??? sidhartha
• 9 years agoHelpfull: Yes(0) No(0)
• value of log is given in the ph question paper
  
• 9 years agoHelpfull: Yes(0) No(0)