Explanation

To solve the equation:

0.03 × 10

Multiply the decimal by 10:

0.03 × 10 = 0.3

Explanation

To convert the given number to a fraction:

3 (72/100) = 3 + 72/100

Combine the whole number and fraction:

3 = 300/100

Add the fractions:

300/100 + 72/100 = 372/100

Simplify the fraction:

372/100 = 186/50

Now, convert the fraction to a decimal:

186/50 = 3.72

Explanation

To solve the equation:

18 1/6 ÷ 2 1/3

First, convert the mixed numbers to improper fractions:

18 1/6 = 109/6

2 1/3 = 7/3

Then, divide the fractions:

(109/6) ÷ (7/3) = (109/6) × (3/7) = 327/42

Simplify the fraction:

327/42 = 109/14

Convert the improper fraction back to a mixed number:

109/14 = 7 11/14

Explanation

Let's evaluate the equation:

(1/4 + 5/8) = 2/8 + 5/8 = 7/8

(1/2 + 3/4) = 4/8 + 6/8 = 10/8 = 5/4

Add the two expressions:

(7/8) + (5/4) = 7/8 + 10/8 = 17/8

So, the equation evaluates to 17/8.

Therefore, the correct answer is 17/8.

Explanation

Explanation

To calculate the total number of handshakes:

Each person shakes hands with 9 others.

There are 10 people, so it seems like there would be 10 x 9 = 90 handshakes.

However, this counts each handshake twice (once for each person involved).

To correct this, divide the total by 2:

90 / 2 = 45

Explanation

To find the ratio, divide the number of red cars by the number of green cars:

42 (red) ÷ 14 (green) = 3

So, for every 1 green car, 3 red cars were sold. Hence, the ratio is 3:1.

Explanation

Explanation

1 kilogram (kg) of gold = 1,000 grams (g)

1 gram (g) of gold = 1,000 milligrams (mg)

1 ounce (oz) of gold ≈ 31.1 grams (g)

A kilogram is equal to 2.2 pound.

Gold density: 19.3 g/cm³

Gold melting point: 1,064°C (1,947°F)

Explanation

Let A's current age be x and B's current age be y.

Since A is twice as old as B, x = 2y.

Three years ago, A's age was x - 3 and B's age was y - 3.

Since A was three times as old as B, x - 3 = 3(y - 3).

Solving the equations, we get x = 12.

So, the correct answer is 12 years.