Estimate the compressive strength of the concrete using average rebound number. Considering the average rebound number, discuss the quality of concrete. First column: Measurements taken for the 0 angle for wall Second column: Measurements taken for the -90 angle on floor 31 29 28 30 21 30 28 20 19 30 Average: 26.6 46 48 50 45 49 43 54 42 55 46 Average: 47.8 O Discard readings differing from the average of 10 readings by more than 6 units and determine the average of the remaining readings. If more than 2 readings differ from the average by 6 units, discard the entire set of readings and determine rebound numbers at 10 new locations within the test area. Use the instrument correlation curve to estimate the compressive strength.