Explanation

Multiplying 3.29 by 1000 gives:

3.29 × 1000 = 3290

Explanation

Given sequence: 4, 11, 7, 14, 10, 17, __, 20

Two alternating series are used:

First series: 4 → 7 → 10 → 13 (+3 each time)

Second series: 11 → 14 → 17 → 20 (+3 each time)

Missing number: 13

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

• Roni covers 100 meters in 45 seconds.
• Willy covers 100 meters in 36 seconds.

1. Roni's speed:

   Speed of Roni=100 m / 45 s​=20​/9 m/s

2. Distance Roni covers in 36 seconds:

   Distance=Speed×Time=20/9​×36=80 m

3. Since Willy finishes the race (100 m) when Roni has only covered 80 m, Willy beats Roni by:

   $$100-80=20\text{ m}$$

Explanation

Six tenths is the same as 6/10, which simplifies to 3/5 or 0.6.

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

The square root of 169 is 13, since 13 multiplied by 13 (13²) equals 169.

Explanation

The series is obtained by multiplying the previous term by a increasing sequence of numbers:

• 2 × 2 = 4
• 4 × 3 = 12
• 12 × 4 = 48
• 48 × 5 = 240
• 240 × 6 = 1440

Explanation

Since 3 is a solution, plug x = 3 into the equation:

3(3)^2 + (k - 1)(3) + 9 = 0

27 + 3k - 3 + 9 = 0

3k + 33 = 0

3k = -33

k = -11

Explanation

As we all know

Circumference of the circle: 2πr

The radius of the circle: r

Ratio = 2πr : r = 2πr/r = 2π

Thus we conclude that 2π:1