# `RethNav.getExchangeRate` exercise Write your code inside the [`RethNav` contract](https://github.com/Cyfrin/defi-reth/blob/main/foundry/src/exercises/RethNav.sol) This exercise is design to implement a function that will calculate the exchange rate of 1 rETH into ETH. ```solidity function getExchangeRate() external view returns (uint256) { // Returns 18 decimals } ``` ## Instructions 1. **Calculate the rETH to ETH exchange rate** - Implement logic to compute the amount of ETH given 1 rETH. > **Hint:** Check the Rocket Pool contracts (`RocketTokenRETH`) for how to fetch the exchange rate. ## Testing ```shell forge test --fork-url $FORK_URL --match-path test/exercise-reth-nav.sol --match-test test_nav -vvv ```