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Start your free trial###### Shariff Matola

2,764 Points# For this challenge, we'd like to know in a range of values from 1 to 100, how many numbers are both odd, and a multiple

Can you help me out on this guys I'm stuck

var results = 20

for n in 1...100 { // Enter your code

```
//End code
```

}

```
var results: [Int] = [20]
for n in 1...100 {
// Enter your code below
// End code
}
```

## 9 Answers

###### Jonathan Ruiz

2,998 PointsThis will make you pass the challenge. I would take look at the videos again or restart some of the older parts of logical operators. Especially for foundational material like this.

```
var results: [Int] = []
for n in 1...100 {
if (n % 2 != 0) && (n % 7 == 0) {
results.append(n)
}
}
```

the logic I wrote earlier would still apply

###### Jonathan Ruiz

2,998 PointsHi Shariff for this challenge you have to get a number and append it to the results array if its odd and a multiple of 7. To check to see if a number is divisible you can use the modulo operator (%) and see if the remainder is 0. If the remainder is 0 then the two numbers are perfectly divisible.

```
let example = 25 % 5
// 5 divides into 25 perfectly 5 times so there is no remainder that means they're perfectly divisible
// to check if a number is a multiple of 7
let randomNumber = 49 % 7 == 0
```

You also check to see if a number is odd. For this one its the same idea using the modulo operator( % ) but you will use the logical operator not equal ( != ). This logical operator means not equal to.

```
let example = 25 % 2 != 0
//if you put this on a playground it will say true on the right hand side because 25 is an odd number.
```

Since these are the two parts of the if statement you write you must combine them with the and logical operator ( && ). If both conditions are true the code executes if even one is not true the code doesn't run.

```
if (49 % 7 == 0) && (25 % 2 != 0) {
}
lastly to append to the results array use dot notation and ( ) to append n to the results array.
```swift
let results: [Int] = [ ]
// we need to put :[Int] since its an empty array and the compiler needs to know the type since this is an empty array
example.append( )
```

hope this helps !

###### Shariff Matola

2,764 PointsThank you but I'm still having challenges on this

###### Jonathan Ruiz

2,998 PointsWhat part is confusing maybe I can explain it differently

###### Shariff Matola

2,764 PointsFor real this part its a beat difficult to me i have almost a week trying to work on it but its kinda trick

###### Shariff Matola

2,764 PointsAt least now i know where its going but im in a war with that

###### Shariff Matola

2,764 PointsCheers l see i was not using .append

###### Jonathan Ruiz

2,998 Pointsah I see yeah at the end they want you to append n to the empty array glad you passed it !

###### Shariff Matola

2,764 PointsYeah Jonathan thank you so much lemme try to work until i reach your level

###### Jonathan Ruiz

2,998 Pointshappy to help learning to code is just time and practice I don't know everything either