Marbles come in two sizes: 1-inch diameter and 2-inch diameter. The 1-inch diameter marbles cost 30 cents less than the 2-inch marbles. Rochelle buys 25 1-inch marbles for her science project and spends exactly $10. Find the cost of a 2-inch marble.(1 point)
Let's assume the cost of a 1-inch marble is x cents.
According to the problem, the cost of a 2-inch marble is x + 30 cents.
Rochelle buys 25 1-inch marbles, so the total cost of the 1-inch marbles is 25x cents.
We also know that the total cost of the 1-inch marbles is $10 or 1000 cents.
So we have the equation: 25x = 1000
Dividing both sides of the equation by 25, we get: x = 40
Therefore, the cost of a 1-inch marble is 40 cents.
The cost of a 2-inch marble is x + 30 = 40 + 30 = 70 cents. Answer: \boxed{70}.