Find the value of 15 x 25 in (mod 8)

$$15 = 1 \times 8 + 7$$

So, $15 \equiv 7 \pmod 8$.

$$25 = 3 \times 8 + 1$$

So, $25 \equiv 1 \pmod 8$.

We need to find the value of $(15 \times 25) \pmod 8$.
Using the property of modular arithmetic, $(a \times b) \pmod m = ((a \pmod m) \times (b \pmod m)) \pmod m$:

$$(15 \times 25) \pmod 8 \equiv (7 \times 1) \pmod 8$$ $$(15 \times 25) \pmod 8 \equiv 7 \pmod 8$$

The value of $15 \times 25$ in (mod 8) is 7.

$$7$$