An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (1)
52486 + (7546 - 5988) = 52486 + 1558 = 54044 .
10000 - 6348 = 3652 oranges.
17556 / 57 = 308 textbooks.
The digit in the tens place of 68370 is 7 .
3 - 1.986 = 1.014 m.
40 * 12.3 = 492 m.
Solving the system of equations gives the smallest number as 8 .
(3/5) * 80 = 48 boys, so 80 - 48 = 32 girls.
14 5 2 ∗ 2 9 7 = 5 72 ∗ 9 25 = 40 .
13 3 2 /30 = 3 41 /30 = 90 41 liters.
0.35 / 100 = 0.0035 .
Explanation
Introduction Let's tackle these word problems one by one! We'll break down each question, perform the necessary calculations, and clearly state the answer.
Question 2i Solution Question 2i: To solve 52486 + (7546 - 5988), we first calculate the value inside the parentheses: 7546 - 5988 = 1558. Then, we add this result to 52486: 52486 + 1558 = 54044.
Question 2iii Solution Question 2iii: Kanani had 10000 oranges and sold 6348. To find how many oranges he has left, we subtract the number of oranges sold from the initial amount: 10000 - 6348 = 3652.
Question 2iv Solution Question 2iv: To find how many textbooks each school received, we divide the total number of textbooks by the number of schools: 17556 / 57 = 308.
Question 2v Solution Question 2v: In the number 68370, the digit in the tens place is 7.
Question 2vi Solution Question 2vi: The carpenter had a 3 m timber and cut a 1.986 m piece. To find the length of the remaining timber, we subtract the length of the cut piece from the original length: 3 - 1.986 = 1.014 m.
Question 3i Solution Question 3i: The electrical engineer bought 40 pieces of wire, each 12.3 m long. To find the total length, we multiply the number of pieces by the length of each piece: 40 * 12.3 = 492 m.
Question 3ii Solution Question 3ii: Let the three numbers be x, y, and z. We have the equations: x + y + z = 48, x = (2/3)y, and z = (1/2)x. Substituting x and z in terms of y, we get (2/3)y + y + (1/2)(2/3)y = 48, which simplifies to (2/3)y + y + (1/3)y = 48. Combining the terms, we have (2/3 + 1 + 1/3)y = 48, which gives (2/3 + 3/3 + 1/3)y = (6/3)y = 2y = 48. Solving for y, we get y = 24. Then, x = (2/3) * 24 = 16, and z = (1/2) * 16 = 8. The smallest number is 8.
Question 3iii Solution Question 3iii: In a class of 80 pupils, 3/5 are boys. The number of boys is (3/5) * 80 = 48. To find the number of girls, we subtract the number of boys from the total number of pupils: 80 - 48 = 32.
Question 4i Solution Question 4i: Joseph multiplied 14 5 2 by 2 9 7 . First, convert the mixed numbers to improper fractions: 14 5 2 = 5 72 and 2 9 7 = 9 25 . Then, multiply the fractions: 5 72 ∗ 9 25 = 5 ∗ 9 72 ∗ 25 = 45 1800 = 40 .
Question 4ii Solution Question 4ii: 13 3 2 liters of milk were shared equally among 30 people. Convert the mixed number to an improper fraction: 13 3 2 = 3 41 . Divide the total amount of milk by the number of people: 3 41 /30 = 3 41 ∗ 30 1 = 90 41 liters.
Question 4iii Solution Question 4iii: To convert 0.35% into a decimal, we divide by 100: 0.35 / 100 = 0.0035.
Examples
These types of math problems are commonly used in everyday situations. For example, calculating discounts while shopping (percentages), dividing quantities equally among people (division), determining remaining amounts after consumption (subtraction), and calculating total lengths or areas (multiplication) are all practical applications of these mathematical concepts. Understanding these basic operations is crucial for managing personal finances, making informed purchasing decisions, and solving various real-world problems.
