Solve the following equations step by step

x + 7 = 4

The chart below shows the distribution of weeds in yard

3× __ -2=15 7 2× __+1=7 5 7× =22 15 5× __+10=2 8 × __+4=20 6 × =10 3 × __+2=8 6 × __+8=8 9 × __+7=20 6

The weight of an object in a particular scale is 175.2 lbs. the measured weight may vary from the actual weight by at most 0.1 lbs. what is the range of actual weights of the object