The sum of the angles in a triangle is always 180°. Given that two angles measure 40° and 70°, we can find the missing angle by subtracting the sum of the given angles from 180°: 180° – (40° + 70°) = 70°. Therefore, the correct answer is  70°.

The probability of randomly selecting a red marble can be calculated by dividing the number of red marbles by the total number of marbles. In this case, there are 8 red marbles and a total of 8 + 4 + 5 = 17 marbles. Therefore, the probability is 8/17. Therefore, the correct answer is 8/17.

To solve for y in the equation 2(y – 4) – 3(2y + 1) = 5, we can start by simplifying both sides of the equation. Distributing 2 to (y – 4) gives us 2y – 8. Distributing 3 to (2y + 1) gives us 6y + 3. The equation now becomes 2y – 8 – 6y – 3 = 5. Combining like terms, we have -4y – 11 = 5. Adding 11 to both sides and dividing by -4, we get y = -4/(-4) = 1. Therefore, the correct answer is  3/4.

To solve for y in the equation 5(y – 3) + 2y = 3(y + 2) – 4, we can start by simplifying both sides of the equation. Distributing 5 to (y – 3) gives us 5y – 15. Distributing 3 to (y + 2) gives us 3y + 6. The equation now becomes 5y – 15 + 2y = 3y + 6 – 4. Combining like terms, we have 7y – 15 = 3y + 2. Subtracting 3y from both sides and adding 15 to both sides, we get 4y = 17. Finally, dividing both sides by 4 gives us y = 17/4. Therefore, the correct answer is 17/4.

The area of a rectangle is calculated by multiplying its length by its width. In this case, the area is 45 square units and the width is 5 units. So, the length is 45 square units / 5 units = 9 units. Therefore, the correct answer is  9 units.

The sum of the angles in a triangle is always 180°. Given that two angles measure 50° and 80°, we can find the missing angle by subtracting the sum of the given angles from 180°: 180° – (50° + 80°) = 50°. Therefore, the correct answer is  50°.

To solve the equation 2x + 7 = 3(x – 4), we can start by simplifying both sides of the equation. Distributing 3 to (x – 4) gives us 3x – 12. The equation now becomes 2x + 7 = 3x – 12. Subtracting 2x from both sides, we have 7 = x – 12. Adding 12 to both sides, we get 19 = x. Therefore, the correct answer is 19.

To solve for x in the equation 3(x + 5) = 2(x – 4) + 9, we start by simplifying both sides of the equation. Distributing 3 to (x + 5) gives us 3x + 15. Distributing 2 to (x – 4) gives us 2x – 8. The equation now becomes 3x + 15 = 2x – 8 + 9. Combining like terms, we have 3x + 15 = 2x + 1. Subtracting 2x from both sides and subtracting 15 from both sides, we get x = -14. Therefore, the correct answer is -14.

To find the value of 4² – 3³ + 5⁰, we simply evaluate each exponent. 4² means 4 raised to the power of 2, which is 16. 3³ means 3 raised to the power of 3, which is 27. 5⁰ means 5 raised to the power of 0, which is 1 (any number raised to the power of 0 is equal to 1). Therefore, the expression becomes 16 – 27 + 1 = -10. Therefore, the correct answer is  -10.

To simplify the expression 1/3 + 2/5 – 3/6, we need to find a common denominator for the fractions. The least common multiple of 3, 5, and 6 is 30. Multiplying the numerator and denominator of each fraction to have a denominator of 30, we get 10/30 + 12/30 – 15/30. Combining the numerators, we have 7/30. Therefore, the correct answer 7/30.

To simplify the expression 1/2 + 2/3 – 3/4, we need to find a common denominator for the fractions. The least common multiple of 2, 3, and 4 is 12. Multiplying the numerator and denominator of each fraction to have a denominator of 12, we get 6/12 + 8/12 – 9/12. Combining the numerators, we have 6 + 8 – 9 = 5. Therefore, the correct answer is 5.

To simplify the expression 2/3 + 1/4 – 5/6, we need to find a common denominator for the fractions. The least common multiple of 3, 4, and 6 is 12. Multiplying the numerator and denominator of each fraction to have a denominator of 12, we get 8/12 + 3/12 – 10/12. Combining the numerators, we have 8 + 3 – 10 = 1. Therefore, the correct answer is 1/12.

To simplify the expression 5 – (2x + 3) + (4 – 3x), we start by removing the parentheses and combining like terms. The expression becomes 5 – 2x – 3 + 4 – 3x. Combining the like terms, we have -5x + 6. Therefore, the correct answer is -5x + 2.

To simplify the expression (2 + 3) × (4 – 1) ÷ 5, we start by performing the addition and subtraction inside the parentheses: (2 + 3) = 5 and (4 – 1) = 3. The expression now becomes 5 × 3 ÷ 5. Then, we perform the multiplication: 5 × 3 = 15. Finally, we perform the division: 15 ÷ 5 = 3. Therefore, the correct answer is  3.

If the price of a book is $24 and it is discounted by 30%, we need to find 30% of $24 and subtract it from the original price. 30% of $24 is (30/100) * $24 = $7.20. Subtracting $7.20 from $24 gives us $24 – $7.20 = $16.80. Therefore, the correct answer is  $16.80.

To solve the equation 3(x – 5) = 2(4 – x) + 9, we can start by simplifying both sides of the equation. Distributing 3 to (x – 5) gives us 3x – 15. Distributing 2 to (4 – x) gives us 8 – 2x. The equation now becomes 3x – 15 = 8 – 2x + 9. Combining like terms, we have 3x – 15 = -2x + 17. Adding 2x to both sides and adding 15 to both sides, we get 5x = 32. Finally, dividing both sides by 5 gives us x =  Therefore, the correct answer is 32/5.

The perimeter of a rectangle is calculated by adding the lengths of all its sides. In this case, the length is 8 units and the width is 3 units. The formula for the perimeter of a rectangle is P = 2(l + w). Plugging in the values, we get P = 2(8 + 3) = 2(11) = 22 units. Therefore, the correct answer is  22 units.

To solve for x in the equation 2(3x + 4) = 5(x – 2) + 7, we can start by simplifying both sides of the equation. Distributing 2 to (3x + 4) gives us 6x + 8. Distributing 5 to (x – 2) gives us 5x – 10. The equation now becomes 6x + 8 = 5x – 10 + 7. Combining like terms, we have 6x + 8 = 5x – 3. Subtracting 5x from both sides and subtracting 8 from both sides, we get x = -11. Therefore, the correct answer is -11.

The area of a square is calculated by multiplying the length of one side by itself. In this case, the area is 64 square units. To find the length of one side, we take the square root of the area. The square root of 64 is 8. Therefore, the correct answer is  8 units.

If the recipe calls for 2/3 cup of sugar and you want to make half of the recipe, you need to multiply 2/3 by 1/2. Multiplying fractions involves multiplying the numerators and multiplying the denominators. So, (2/3) × (1/2) = 2/6 = 1/3. Therefore, you need 1/3 cup of sugar. Therefore, the correct answer is 1/3 cup.

The perimeter of a square is calculated by multiplying the length of one side by 4 since a square has four equal sides. In this case, the perimeter is 32 cm. So, the length of each side is 32 cm / 4 = 8 cm. Therefore, the correct answer is 8 cm.

To simplify the expression 4(2x + 3) – 2(3x – 5), we start by distributing the coefficients. This gives us 8x + 12 – 6x + 10. Combining the like terms, we have 2x + 22. Therefore, the correct answer is  2x + 22.

If a shirt originally costs $25 and it is discounted by 20%, we can calculate the sale price by multiplying the original price by (1 – 0.20). So, the sale price is $25 * (1 – 0.20) = $25 * 0.80 = $20. Therefore, the correct answer is  $20.

To solve the equation 2(y + 4) + 3(y – 5) = 4(y – 2) + 5, we can start by simplifying both sides of the equation. Distributing 2 to (y + 4) gives us 2y + 8. Distributing 3 to (y – 5) gives us 3y – 15. Distributing 4 to (y – 2) gives us 4y – 8. The equation now becomes 2y + 8 + 3y – 15 = 4y – 8 + 5. Combining like terms, we have 5y – 7 = 4y – 3. Subtracting 4y from both sides and adding 7 to both sides, we get y = 4. Therefore, the correct answer is  2.