Explanation

This is a distance problem using the Pythagorean theorem.

A person moves:

• 80 km North
• 60 km West

These form a right triangle.

Distance from starting point:

d=  √(80^2 + 60^2)

=√(6400 + 3600)

= √(10000) 

= 100 km

Last updated question by NS on 2 MAY 2026

Explanation

Assume originally:

• Bought 100 items for Rs.100
  So, Cost Price (CP) per item = Rs.1

Now buys 10% less:

• 10% less than 100 = 90 items
• Still spends Rs.100

So new CP per item:

CP= 100/90​

Now sells 10% more:

• 10% more than 100 = 110 items

Assume selling rate is Rs.1 per item.

So total Selling Price:

$$SP=110\times 1=110$$

Profit:

$$Profit=SP-CP=110-100=10$$

Profit percentage formula:

$$\text{Profit \%}=$$Profit/ Cost Price ​×100

Substitute values:

10/100​×100=10%

That approach looks tempting, but it ignores that buying fewer changes the cost per item. The correct combined effect is:

Profit %=(110/90​−1)×100

$(110/90-1)\times 100$

$$=left(frac{20}{90}right)times100$$$$=22.22$$

$$Last\; updated\; question\; by\; NS\; on\; 2\; MAY\; 2026$$

Explanation

To find a single equivalent discount, we apply successive discounts step by step.
Assume original price = 100
Step 1: 10% discount
100 → 90
Step 2: 20% discount on 90
90 → 72
Step 3: 40% discount on 72
72 → 43.2
Final price = 43.2
Total discount:
100 − 43.2 = 56.8

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Last updated by NS on 01 MAY 2026

Explanation

In this series, each number is formed by adding the square of a natural number (1^2, 2^2, 3^2, .....) to the preceding number.

• 15 + 1² = 16
• 16 + 2² = 20
• 20 + 3² = 29 ← should be 29, but given 30
• 29 + 4² = 45
• 45 + 5² = 70

So the correct sequence should be:

15, 16, 20, 29, 45, 70

Therefore, 30 is the incorrect number

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Last updated by NS on 01 MAY 2026

Explanation

This is a geometric progression (GP) where each term is multiplied by 3:

1, 3, 9, 27, 81, 243, 729, 2187

Formula:

Here:

• a = 1
• r = 3
• n = 8

So:

8th term = 2187

Last updated by NA on 2 MAY 2026