[Measurements] Fix small typo in workbook for task 1.3 (#402)

Measurements/Workbook_Measurements.ipynb

@@ -160,7 +160,7 @@
    "source": [
     "### Solution\n",
     "\n",
-    "Both input state are superposition states, with equal absolute values of amplitudes of both basis states. This means if the sate is measured in the Pauli $Z$ basis, like we did in the previous task, there is a 50-50 chance of measuring `One` or `Zero`, which won't give us the necessary information.  \n",
+    "Both input states are superposition states, with equal absolute values of amplitudes of both basis states. This means if the sate is measured in the Pauli $Z$ basis, like we did in the previous task, there is a 50-50 chance of measuring `One` or `Zero`, which won't give us the necessary information.  \n",
     "\n",
     "To determine in which state the input qubit is with certainty, we want to transform the qubit into a state where there is no superposition with respect to the basis in which we perform the measurement. \n",
     "\n",