How many 4-letter combinations containing 3 consonants and 1 vowel can be made from this set if all the letters in a combination must be unique? {R, E, L, O, A, D}

150 four-letter strings can be formed.

Step-by-step explanation:

A. The probability that a person older  than 35 years has a hemoglobin

level less than 9 is 76/162 or 0.47 (rounding to two decimal places)

B. The probability that a person  younger than 25 years has a  hemoglobin level above 11 is 69/139 or 0.50 (rounding to two decimal places).

C. The probability that a person in the  25–35 age group has a hemoglobin  level less than 9 is 32/128 or 0.25.

D. The probability that a person older  than 35 years has a hemoglobin  level between 9 and 11 is 46/162 or 0.28 (rounding to two decimal places).

Step-by-step explanation:

1. Let's review the information given to solve these questions:

The people surveyed were grouped in three range of ages: less than 25 years , 25 to 35 years and over 35 years. Related to the hemoglobin level, the ranges were also three: less than 9, between 9 and 11 and above 11.

Total of persons surveyed = 429

Less than 25 surveyed = 139

Between 25 and 25 years old = 128

Older than 35 = 162

From the less than 25 surveyed people, 21 had hemoglobin less than 9, 49 between 9 and 11 and 69 had above 11 of hemoglobin level.

From the 25 to 35 surveyed people, 32 had hemoglobin less than 9, 52 between 9 and 11 and 44 had above 11 of hemoglobin level.

Finally, from the group of people above 35 years,  76 had hemoglobin less than 9, 46 between 9 and 11 and 40 had above 11 of hemoglobin level.

2. Now let's drag the tiles to the correct boxes to complete the pairs.

A. The probability that a person older  than 35 years has a hemoglobin

level less than 9 is 76/162 or 0.47 (rounding to two decimal places)

B. The probability that a person  younger than 25 years has a  hemoglobin level above 11 is 69/139 or 0.50 (rounding to two decimal places).

C. The probability that a person in the  25–35 age group has a hemoglobin  level less than 9 is 32/128 or 0.25.

D. The probability that a person older  than 35 years has a hemoglobin  level between 9 and 11 is 46/162 or 0.28 (rounding to two decimal places).