మనం ఈ ప్రశ్నను ఒక్కొక్కదిగా అర్థం చేసుకొని, సరైన సంఖ్యలను కనుగొంటాం.
Step 1: Let the 7 distinct even natural numbers be in ascending order:
Let the 7 numbers be:
a < b < c < d < e < f < g
(ఇవి అన్నీ సరి సంఖ్యలు, అంటే even numbers)
Step 2: Average of all 7 numbers is 26
So their sum = 7 × 26 = 182
Step 3: Average of least two numbers is 16
⇒ (a + b)/2 = 16
⇒ a + b = 32
Step 4: Average of largest two numbers is 36
⇒ (f + g)/2 = 36
⇒ f + g = 72
Step 5: Sum of smallest and largest is 52
⇒ a + g = 52
Now use these to find values step-by-step
We know:
a + b = 32
…(1)f + g = 72
…(2)a + g = 52
…(3)- total sum =
a + b + c + d + e + f + g = 182
…(4)
From (3): a + g = 52
So from this: g = 52 - a
…(5)
Substitute (5) in (2):
f + (52 - a) = 72
⇒ f = 72 - 52 + a = 20 + a
…(6)
From (1): a + b = 32
⇒ b = 32 - a
…(7)
Now total sum:
a + b + c + d + e + f + g = 182
Substitute values from (5), (6), (7):
a + (32 - a) + c + d + e + (20 + a) + (52 - a) = 182
⇒ 32 + c + d + e + 20 + 52 = 182
⇒ c + d + e + 104 = 182
⇒ c + d + e = 78
Step 6: Given that squares of middle 3 numbers (c, d, e) = 2084
So:
c² + d² + e² = 2084
…(8)
And:
c + d + e = 78
…(9)
Let’s try suitable even numbers c < d < e
which add up to 78 and check their squares.
Try:
c = 24, d = 26, e = 28
⇒ sum = 78
Check squares:24² + 26² + 28² = 576 + 676 + 784 = 2036 ❌
Try:
c = 22, d = 26, e = 30
⇒ sum = 78
Squares =484 + 676 + 900 = 2060 ❌
Try:
c = 20, d = 26, e = 32
⇒ sum = 78
Squares =400 + 676 + 1024 = 2100 ❌
Try:
c = 22, d = 24, e = 32
⇒ sum = 78
Squares =484 + 576 + 1024 = 2084 ✅
Perfect!
So c = 22, d = 24, e = 32
Now total 7 numbers:
- We already found:
a = ?
b = ?
c = 22
d = 24
e = 32
f = 20 + a
[from (6)]g = 52 - a
[from (5)]
We also know a + b = 32
⇒ try values of a that make all numbers distinct and even.
Try a = 12
⇒ b = 20
, f = 32
, g = 40
Now list all:
a=12, b=20, c=22, d=24, e=32, f=32, g=40
But e = 32
and f = 32
⇒ not distinct
Try a = 10
⇒ b = 22
, already c=22 ⇒ conflict
Try a = 8
⇒ b = 24
, but d = 24 ⇒ conflict
Try a = 14
⇒ b = 18
, f = 34, g = 38
Now list:
- a = 14
- b = 18
- c = 22
- d = 24
- e = 32
- f = 34
- g = 38
Check:
- All even ✅
- All distinct ✅
- In increasing order ✅
- a + b = 32 ✅
- a + g = 52 ✅
- f + g = 72 ✅
- c + d + e = 78 ✅
- c² + d² + e² = 2084 ✅
- Total sum = 182 ✅
Perfect!
Now Final Step:
Numbers in increasing order:
14, 18, 22, 24, 32, 34, 38
Now, counting from the largest:
1st → 38
2nd → 34
3rd → 32
✅ Final Answer: 32
👉 గరిష్ఠ సంఖ్య నుండి లెక్కిస్తే మూడవ సంఖ్య 32.
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