A designed experiment is described. Identify the specified element. In a clinical trial, 780 participants suffering from high blood pressure were randomly assigned to one of three groups. Over a one-month period, the first group received a low dosage of an experimental drug, the second group received a high dosage of the drug, and the third group received a placebo. The diastolic blood pressure of each participant was measured at the beginning and at the end of the period and the change in blood pressure was recorded. Identify the levels of the factor. Group of answer choices

234

Step-by-step explanation:

Let the digit in the hundreds place be a, the digit in the tens place be b and the digit in the ones place be c. So a b c is the number.

(Based on the question) a + b + c = 9 Equation 1

From Equation 1, you can get:

2a + 2b + 2c = 18 Equation 2

(Based on the question) 2b = a + c Equation 3

(Based on the question) 2a = c Equation 4

Replace the c in Equation 3 with Equation 4:

2b = a + 2a

Evaluate.

2b = 3a Equation 5

Replace all the values of b and c with Equations 4 and 5 respectively into Equation 1 (Check underlined Equations to realise that all terms equal to a term in a):

2a + 3a + 2(2a) = 18

Evaluate.

2a + 3a + 4a = 18

9a = 18

Find a.

a = 18 ÷ 9

a = 2

Based on Equation 4, find c.

c = 2 × 2

c = 4

Based on Equation 1, find b.

b = 9 - 2 - 4

b = 3

Piecing together the values of a, b and c, the number is 234.