Question

Karim sent a chain email to
\[10\] of his friends. The number of people who got the email increases by a factor of
\[1.4\] every week.
Which expression gives the number of people who got the email after
\[6\] weeks?
Choose 1 answer:
Choose 1 answer:
(Choice A)
\[10\cdot 1.4^6\]
A
\[10\cdot 1.4^6\]
(Choice B)
\[(10\cdot 1.4)^6\]
B
\[(10\cdot 1.4)^6\]
(Choice C)
\[(10+1.4)\cdot 6\]
C
\[(10+1.4)\cdot 6\]
(Choice D)
\[10+1.4\cdot 6\]
D
\[10+1.4\cdot 6\]

Answer 1

To determine which expression represents the number of people who got the email after 6 weeks, we start with the given information:

- Karim initially sent the email to \(10\) friends.
- Each week, the number of people who received the email increases by a factor of \(1.4\).

This means that after each week, the total number of people who received the email can be calculated by multiplying the previous number of recipients by \(1.4\).

After:
- Week 1: \(10 \times 1.4\)
- Week 2: \(10 \times 1.4^2\)
- Week 3: \(10 \times 1.4^3\)
- Week 4: \(10 \times 1.4^4\)
- Week 5: \(10 \times 1.4^5\)
- Week 6: \(10 \times 1.4^6\)

Thus, after \(6\) weeks, the expression for the number of people who got the email is:

\[
10 \cdot 1.4^6
\]

This matches with **Choice A**:

(Choice A) \[10 \cdot 1.4^6\]

Therefore, the correct answer is **Choice A**.