#1 - Make Equation Correct Riddle

Can you replace each alphabet with the number (1 - 9) to make below equation correct ?

AB * C = DE - F = GH / I

39 * 1 = 45 - 6 = 78 / 2

AB - C = DE / F = GH * I can be solved as
A = 3
B = 9
C = 1
D = 4
E = 5
F = 6
G = 7
H = 8
I = 2

So below equation can be solved as:
AB - C = DE / F = GH * I
39 * 1 = 45 - 6 = 78/2
39 = 39 = 39.


#2 - Roman Number Equation Problem

Considering below equation holds

V + II - VI = 10
IV - X + VIII = 20
IV - VII + VI = 30

Then, I + II + III = ?

60

V + II - VI = 10
=> I = 10

IV - X + VIII = 20
=> II = 20

IV - VII + VI = 30
=> III = 30

I + II + III = 10 + 20 + 30

#3 - Replace Question Mark Equation

Can you replace question mark to make the below equation true ?

16 ? 14 ? 4 ? 6 = 62

16 14 / 4 + 6 = 62

#4 - Answer Fast Equation Riddle

If
20 % 5 = 24

21 % 7 = 33

42 % 6 = 67

Then;

66 % 6 = ?

1211
The number on the right side is formed as (sum of digits of the 1st number)(number1/number2)
example,
20 % 5 = 24 (2+0)(20/4)
21 % 7 = 33 (2+1)(21/7)
42 % 6 = 67 (4+2)(42/6)

Simillarly,
66 % 6 = 1211 (6+6)(66/6)

#5 - Festive Offer Discount Puzzle

On the occasion of Christmas, Major online seller companies in India is offering big discount on Iphone7 as below.

: Flipkart offers Flat 65% discount
: Amazon offers 10% discount over and over again.
: eBay offers RS 45,000 off.

If the original cost of iPhone is Rs. 70,000 Which is the best offer for you ?

Amazon

Explanation:
Amazon : 24407.490807, Flipkart: 24500 and EBay: 25000

EBay discount :
70000 - 45000 = 25000

Flipkart 65% discount :
35/100 * 70000 = 24500

Amazon 10% recursive discount:
After 1st 10% discount, Amount is 63000
After 2nd 10% discount, Amount is 56700
After 3rd 10% discount, Amount is 51030
After 4th 10% discount, Amount is 45927
After 5th 10% discount, Amount is 41334.3
After 6th 10% discount, Amount is 37200.87
After 7th 10% discount, Amount is 33480.783
After 8th 10% discount, Amount is 30132.7047
After 9th 10% discount, Amount is 27119.43423
After 10th 10% discount, Amount is 24407.490807

#6 - Fun Algebra Puzzle

The following alphametic has only one solution. Can you find it?
ENLIST + SILENT + LISTEN = ANAGRAM

PS: You may start the number from 0.

Since leading a number with 0 is allowed, it can be the only possible solution:
547809 + 087549 + 780954 = 1416312

#7 - Number Pyramid Puzzle

In the attached picture, you will find a pyramid formation, that is made up of ten circles. If you can move only 3 circles, can you turn it upside down?We have numbered the coins so that you can comment the numbers as answers.

Number Pyramid Puzzle

If you move the circles 1, 7 and 10 as shown in the image, you can turn it upside down.


#8 - The Classic Bank Riddle

In a certain bank, a man deposits a certain amount. According to the bank policies, the amount will get doubled up in a year but as the service charge, they will also deduct Rs. 65 by the end of every year.

If after the 6th year, the amount becomes 0, what do you think is the original amount he deposited in the bank?

This is totally impossible in real because you do not pay in bank in fractions. However, the only possible answer is explained below:

Year Amount Interest and Deduction
Start 63.984375
Y1 End 62.968750 63.984375 * 2 - 65
Y2 End 60.937500 62.96875* 2 - 65
Y3 End 56.875000 60.9375 * 2 - 65
Y4 End 48.750000 56.875 * 2 - 65
Y5 End 32.500000 48.75 * 2 - 65
Y6 End 0.000000 32.5 * 2 - 65 = 0

#9 - Dollar Quarter Equation Riddle

A quarter is one fourth of a dollar but Mr. Brainteaser has changed the equation as below :

DOLLAR * 4 = QUARTER

Can you replace each letter by a digit to make above solution correct ?

DOLLAR * 4 = QUARTER
457730 * 4 = 1830920

#10 - Happy Diwali Maths Riddle

Replace the alphabet with the number such that below equation hold true.

HAPPY
+ DIWALI
--------------
HDLALA
--------------

35997
+ 284508
-------------
320505
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