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Angad Singh Marwaha from Shiv Nadar School, Noida

Subject :IMO Class : Class 10

Let ABC be a right angled triangle in which AB = 3 cm, BC = 4 cm and ∠B = 90°. BD is the perpendicular from B on AC. The circle through B, C, D is drawn.
Given below are steps of construction of tangents from A to this circle. Identify the wrong step. Steps of construction :
Step I : Draw ΔABC and perpendicular BD from B on AC.
Step II : Draw a circle with BC as a diameter. This circle will pass through D.
Step III : Let O be the mid point of BC. Join AO.
Step IV : Draw a circle with AO as radius. This circle cuts the circle drawn in step II at B and P.
Step V : Join AP. AP and AB are desired tangents drawn from A to the circle passing through B, C and D.

AOnly I
BOnly IV
COnly III
DOnly V

AO should be the diameter, and not the radius, hence Step IV is incorrect.

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SV YUVINRAJ from RISHS, MANGADU

Subject :IMO Class : Class 3

Mohan made the given picture graph to show the number of birds he counted on a field trip.

What is the total number of Starlings, Crows and Blue Jay Mohan counted?

A4
B8
C12
D16

while starting the test it shows only Robin birds to count. But while reviewing answer it shows above lot of birds to count

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Vishwesh Raul from Parle Tilak, Mumbai

Class : Class 4

this is impossible

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Sushama Saroj from Studyhall, Lucknow

Subject :IMO Class : Class 3

Mohan made the given picture graph to show the number of birds he counted on a field trip.

What was the total number of Robin birds that Mohan counted?

A4
B8
C12
D16

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Ans 1:

Vedang Pandey from DPS SECTOR -45 GURUGRAM, Haryana

Class : Class 2

Ans 2:

Sushama Saroj from Studyhall, Lucknow

Class : Class 3

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Satyam Jha from , Muzaffarpur

Subject :IMO Class : Class 8

The thickness of a hollow metallic cylinder is 2 cm. It is 70 cm long with outer radius of 14 cm. Find the volume of the metal used in making the cylinder, assuming that it is open at both the ends. Also find its weight if the metal weighs 8 g per cm³.

A10440 cm³, 91250 g
B13440 cm³, 90000 g
C11440 cm³, 91520 g
DNone of these

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Hareesh venkatesh from Smt Ramkumari Fomra Vivekananda Vidyalaya, Chennai

Subject :IMO Class : Class 4

A shopkeeper mixed kg of white rice with kg of brown rice. He packed them into 5 packets of equal weight. What was the weight of each packet of rice?

A2 Kg
B3 Kg
C4 Kg
D5 Kg

You people think 20 kg is the answer but we have to divide it by 5 so the correct answer is 4 kg which is C.

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Hareesh venkatesh from Smt Ramkumari Fomra Vivekananda Vidyalaya, Chennai

Class : Class 5

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Hridyansh Goyal from DAV Model School, IIT Kharagpur , Kharagpur

Subject :IMO Class : Class 3

If × = 100, ÷ 2 = and + + + + = 100 ÷ , then find the value of .

A25
B10
C5
D4

Only 10*10 gives 100 so option B is only feasible solution. However, the answer is D that 4. Can anyone help on how to solve this?

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Rishit Mathur from Apeejay Noida, Delhi

Subject :IMO Class : Class 9

In a school, there are 40 students in which boys and girls are in the ratio 3 : 1. The mean age of the boys is 20 years and the mean age of the girls is 18 years. If there is increase in girls by 5 and decrease in boys by 10, then find the new average age (approx.) when the students joining or leaving doesn't change the average age of boys and girls respectively.

A 15 years
B 19 years
C 16 years
D Can't say

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Amrit Shankar Pandey from Kendriya Vidyalaya No.1 Tambaram, Tambaram

Subject :IMO Class : Class 5

Find the difference between the greatest and the smallest 8-digit numbers formed by using the digits 7, 4, 2, 8, 6, 1, 5, 0 (using each digit only once).

A77408532
B7470838
C6434534
D57408532