At Least 4 Batsmen & 4 Bowlers? Count Selections FAST ⚡

 

❓ Question

From a group of 7 batsmen and 6 bowlers, 10 players are to be chosen for a team, which should include:

at least 4 batsmen
at least 4 bowlers
and MUST include one batsman (captain) and one bowler (vice-captain)

Find the total number of ways such a team can be selected.


🖼️ Question Image

At Least 4 Batsmen & 4 Bowlers? Count Selections FAST ⚡


✍️ Short Solution

This is a classic combinations + constraints problem.

👉 Since captain (batsman) and vice-captain (bowler) must be selected, we include them first — then count valid ways to choose the remaining players abiding by the minimum batsman–bowler rule.


🔹 Step 1 — Fix the compulsory players

We must include:

  • 1 batsman (captain)

  • 1 bowler (vice-captain)

So:

Players already selected=2\text{Players already selected} = 2

Remaining to choose:

102=810 - 2 = 8

🔹 Step 2 — Update available players

After fixing the captain & vice-captain:

  • Remaining batsmen = 71=67 - 1 = 6

  • Remaining bowlers = 61=56 - 1 = 5


🔹 Step 3 — Apply “at least 4” condition

Total batsmen in final team ≥ 4

Since 1 batsman is fixed, we need:

Extra batsmen b3\text{Extra batsmen } b \ge 3

Similarly for bowlers:

Extra bowlers w3\text{Extra bowlers } w \ge 3

And total chosen now must be 8:

b+w=8b + w = 8

🔹 Step 4 — Solve possible distributions

List valid integer solutions satisfying all conditions:

Extra Batsmen bb
Extra Bowlers ww
Valid?
35
44
53
62❌ (bowlers < 4)

So only three valid cases.


🔹 Step 5 — Count selections case-wise

We use combinations:

nCr=(nr){}^nC_r = \binom{n}{r}

Case 1: b=3, w=5b = 3,\ w = 5

(63)×(55)=20×1=20\binom{6}{3} \times \binom{5}{5} = 20 \times 1 = 20

Case 2: b=4, w=4b = 4,\ w = 4

(64)×(54)=15×5=75\binom{6}{4} \times \binom{5}{4} = 15 \times 5 = 75

Case 3: b=5, w=3b = 5,\ w = 3

(65)×(53)=6×10=60\binom{6}{5} \times \binom{5}{3} = 6 \times 10 = 60

🔹 Step 6 — Add all valid selections

20+75+60=15520 + 75 + 60 = 155

At Least 4 Batsmen & 4 Bowlers? Count Selections FAST ⚡

✅ Final Answer

155\boxed{155}

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