Meera was playing with her brother using 55 blocks.She gets bored playing and starts arranging the blocks such that the no. of blocks in each row is one less than that in the lower row. Find how many were there in the bottom most row?

• let the the no of block in bottom is n.as,in the upper row the block no is 1 lesser than the lower low.so,
  n*(n+1)/2=55
  (n-10)(n+11)=0
  so,n=10
• 13 years agoHelpfull: Yes(13) No(1)
• 10.
  (10+9+8+...+1)=55.
  A statement to be remembered ,it it useful in solving these and lots more kind of questions.
• 13 years agoHelpfull: Yes(6) No(0)
• She starts with 1 ast the bottom most such that :
  1+2+3+4 . . . +10 = 55.
  Hence there is 1 block at the bottom
• 13 years agoHelpfull: Yes(5) No(2)
• total no. of blocks=55 A/Q;Meera has to arrange it in descending order from bottom. let the no. of blocks at the bottom most row be x. If she starts arranging the blocks in descending order(A/Q) then no. of blocks in the nxt row will be (x-1), then in nxt row it will be (x-2). Similarly the top most row will have only 1 block.
  As we know the sum of first x natural numbers = [x(x+1)]/2
  So, here x(x+1)/2= 55
  On solving, we get x=10.
  Hence the no. of blocks in the bottom most row= 10.
  
  Ans=10.
• 13 years agoHelpfull: Yes(5) No(0)
• can not b determined...........
  u must tell if the sequence goes upto 1..else solution can b
  
  28, 27... ( 2 rows ) if no such conditon..
  and if contion is there..
  n*(n+1)/2=55
  (n)(n+1)=110
  so,n=10.....
• 13 years agoHelpfull: Yes(4) No(0)
• 10+9+8+....+1=55
• 13 years agoHelpfull: Yes(2) No(0)
• 9+10+11+12+13=55
  so bottom most row has 13 boxes
• 13 years agoHelpfull: Yes(0) No(5)