Both when running the example code in the inline IDE and also in the browser's console, the following expressions result in undefined being printed:

// exercise 1.1.6
const a = 3; // prints undefined

// exercise 1.1.7
const b = a + 1; // prints undefined

In the solutions, the values listed are 3 and 4 respectively. Which, given the results above, is incorrect.

The expressions that do result in 3 and 4 would be:

a = 3; // prints 3
b = a + 1; // prints 4

See attached screenshots for proof.

inline IDE results

console results

console corrected results