Conditional expectation for exponential random variables

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A man puts his house for sale, and decides to accept the first offer that exceeds the reserve price of $£r$. Let $X_1,X_2,...$ represent the sequence of offers received, and suppose that the $X_i$ are independent and identically distributed random variables, each having exponential distribution with rate parameter $\lambda$.
(1) What is the expected number of offers received before the house is sold?
(2) What is the expected selling price of the house?

For the first part I got $E[N]=e^{\lambda r}$ where $N$ is the number of offers before the house is sold.
For the second part I think I need to do the conditional expectation for $E(X|X\gt r)$?