Translate each sentence into an equation.
1.
three more than four times a number is equal to twelve.
2.
the sum of a number and two is twice the number.
3.
the quotient of a number and twelve is the sum of eight and the number.
4.
five more than three times a number is equal to eight.
5.
the sum of a number and six is seven times the number.
6.
the quotient of a number and six is equal to nine.
7.
seven less than a number is two.
8.
twenty-seven is the product of three and a number.
9.
twelve less than six times a number is equal to three times the number.

Farmers know that driving heavy equipment on wet soil compresses the soil and injures future crops. here are data on the "penetrability" of the same type of soil at two levels of compression. penetrability is a measure of how much resistance plant roots will meet when they try to grow through the soil. compressed soil 2.85 2.66 3 2.82 2.76 2.81 2.78 3.08 2.94 2.86 3.08 2.82 2.78 2.98 3.00 2.78 2.96 2.90 3.18 3.16 intermediate soil 3.17 3.37 3.1 3.40 3.38 3.14 3.18 3.26 2.96 3.02 3.54 3.36 3.18 3.12 3.86 2.92 3.46 3.44 3.62 4.26 use the data, omitting the high outlier, to give a 95% confidence interval for the decrease in penetrability of compressed soil relative to intermediate soil. compute degrees of freedom using the conservative method. interval: to