Ventura Coal mined 6 ⅔ tons on Monday, 7 ¾ tons on Tuesday, and 4 ½ tons on Wednesday. If the goal is to mine 25 tons this week, how many more tons must be mined?

Change to decimals.

25 - 6.67 - 7.75 - 4.5 = ?

6.08

To find out how many more tons must be mined to reach the goal of 25 tons, we need to add up the tons mined on each day and subtract it from the goal. Let's calculate it step by step:

On Monday, Ventura Coal mined 6 ⅔ tons. To add this mixed number with a whole number, we need to convert the mixed number to an improper fraction. To convert 6 ⅔ to an improper fraction, multiply the whole number part (6) by the denominator (3), and add it to the numerator (2). So, 6 ⅔ is equal to (6 * 3) + 2 = 20/3 tons.

On Tuesday, they mined 7 ¾ tons. Similar to Monday, we convert 7 ¾ to an improper fraction. Multiply the whole number part (7) by the denominator (4), and add it to the numerator (3). So, 7 ¾ is equal to (7 * 4) + 3 = 31/4 tons.

On Wednesday, they mined 4 ½ tons. Converting 4 ½ to an improper fraction, we get (4 * 2) + 1 = 9/2 tons.

Now, let's add up the amounts mined each day:
20/3 + 31/4 + 9/2

To perform addition with fractions, we need to find a common denominator. The least common multiple (LCM) of 3, 4, and 2 is 12.

Converting each fraction to have the denominator of 12:
(20/3) * (4/4) = 80/12
(31/4) * (3/3) = 93/12
(9/2) * (6/6) = 54/12

Now, adding the fractions:
80/12 + 93/12 + 54/12 = (80 + 93 + 54)/12 = 227/12 tons

To determine how many more tons must be mined to reach the goal of 25 tons, we subtract the sum of tons mined from the goal:
25 - (227/12)

To subtract a fraction from a whole number, we need to convert the whole number to a fraction with the same denominator as the fraction. So, 25 is equivalent to 25/1.

Performing subtraction with fractions:
25/1 - 227/12

To subtract fractions, we need a common denominator, which is 12:
(25/1) * (12/12) - (227/12) = 300/12 - 227/12 = 73/12 tons

Therefore, Ventura Coal must mine an additional 73/12 tons to reach the goal of 25 tons.