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venkat from narayan school, chenai
Subject :IMO    Class : Class 3

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Ved Sinha from DL DAV MODEL SCHOOL, New Delhi
Subject :IMO    Class : Class 8

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Hryday18 from Greenwood Public School, Gurugram
Subject :IMO    Class : Class 6

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A V from Bombay Scottish School, Mumbai
Subject :IMO    Class : Class 7

A number consists of two digits whose sum is 9. If 27 is added to the number, its digits are interchanged. Given below are the steps to find the number. Identify the wrong step.
Step 1 : Let the unit’s digit be x.
Step 2 : Then, ten’s digit = (9 - x)

∴ Number = 10 × (9 - x) + x ÷ 90 - 10x + x = (90 - 9x)
Step 3 : Adding 27 to the number 90 - 9x we get 117 - 9x
Step 4 : Number with digits interchanged is 10x + (9 - x)= 9x + 9
Step 5 :127 - 9x= 9x + 9
Step 6 : Therefore unit’s digit = 6 and ten’s digit = 3
Step 7 : Hence the number = 36.

A Step 7
B Step 5
C Step 4
D Step 3 and step 6


the division sign in the number step (step before step 3) should be changedthat is the first mistake

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Samriddhi Debnath from Garden High School, Kolkata
Subject :IMO    Class : Class 3

Ans 1:

Samriddhi Debnath from Garden High School, Kolkata
Class : Class 3
C

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Divisha Agarwal from DPS Noida, Noida
Subject :IMO    Class : Class 7

Ans 1:

Gauri Singh from St Johns School Marhauli, Varanasi
Class : Class 8
Answer is option D

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bpa from kvs, mumbai
Subject :IMO    Class : Class 5

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Rupam Das from Krishnanagar High School, NADIA
Subject :IMO    Class : Class 6

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Mohan Tiwari from Shanti niketan, Kolhapur
Subject :IMO    Class : Class 7

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Samriddhi Debnath from Garden High School, Kolkata
Subject :IMO    Class : Class 3

Ans 1:

Samriddhi Debnath from Garden High School, Kolkata
Class : Class 3
Answer:A

Ans 2:

Samriddhi Debnath from Garden High School, Kolkata
Class : Class 3
P=2Q=6R=4S=84*8=32-6=26/2=13Answer:A

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