1. **Problem statement:** Josh starts with a whole number (not 8 or 11) and counts by a whole number (not 5). Some of his numbers are 11, 32, and 46, but 24 is not one of his numbers. We need to find Josh's starting number.
2. **Understanding the problem:** Josh's numbers form an arithmetic sequence: $$a, a+d, a+2d, a+3d, \ldots$$ where $a$ is the starting number and $d$ is the step size.
3. **Given:**
- $a \neq 8$ and $a \neq 11$
- $d \neq 5$
- The sequence contains 11, 32, and 46
- The sequence does not contain 24
4. **Use the arithmetic sequence formula:**
$$a + nd = \text{terms in the sequence}$$
5. **Set up equations for known terms:**
Let $n_1, n_2, n_3$ be integers such that:
$$a + n_1 d = 11$$
$$a + n_2 d = 32$$
$$a + n_3 d = 46$$
6. **Find differences:**
$$32 - 11 = 21 = (n_2 - n_1)d$$
$$46 - 32 = 14 = (n_3 - n_2)d$$
7. **Since $d$ divides both 21 and 14, $d$ must be a common divisor of 21 and 14 other than 5.**
8. **Common divisors of 21 and 14:** 1, 7, and their negatives. Since $d \neq 5$, try $d=7$.
9. **Check $d=7$:**
$$n_2 - n_1 = \frac{21}{7} = 3$$
$$n_3 - n_2 = \frac{14}{7} = 2$$
10. **Find $a$ using $a + n_1 d = 11$:**
Try $n_1=0$ (starting point at 11): $a=11$ (not allowed).
Try $n_1=1$: $a = 11 - 7 = 4$ (allowed).
11. **Check if 24 is in the sequence starting at 4 with step 7:**
$$4 + kd = 24 \Rightarrow 4 + 7k = 24 \Rightarrow 7k = 20 \Rightarrow k = \frac{20}{7}$$ not an integer, so 24 is not in the sequence.
12. **Conclusion:** Josh starts at 4 and counts by 7.
**Final answer:** Josh starts with **4**.
Josh Start 7E38C5
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