Call the "number" x. "The product of 2.5 and a number" is 2.5x. "minus 4.7" makes that 2.5x- 4.7. And that "= 10.3". So the equation is
2.5x- 4.7= 10.3.
To solve that, do the opposite of "multiply by 2.4 and subtract 4.7" in the opposite order. That is, first add 4.7 to both sides. What does that give you?
The divide both sides by 2.5.
