It is very cold today in Tokyo.
TV said today was the last day less than 10 degrees Celsius.

The basic pattern of comparison in Japanese is as below.

A Wa B Yori C Desu

(AはBよりCです。)
This sentence means
A is more C than B.

Let’s make some examples.

Watashi Wa Kere Yori Wakai Desu
(わたしはかれよりわかいです。)
I am younger than him.

Are Wa Kore Yori Oishii Desu
(あれはこれよりおいしいです。)
That is more tasty than this.

Amerika Wa Nihon Yori Hiroi Desu
(アメリカはにほんよりひろいです。)
America is larger than Japan.

This sentence has a basic structure as below.

As you see this is A=B expression.

The part “B Yori(Bより)” means “than B“.

From this understanding you can make a question form easily.
(See A=B? expression page.)

Watashi Wa Kere Yori Wakai Des Ka
(わたしはかれよりわかいですか。)
Am I younger than him?

Are Wa Kore Yori Oishii Desu Ka
(あれはこれよりおいしいですか。)
Is that more tasty than this?

Amerika Wa Nihon Yori Hiroi Desu Ka
(アメリカはにほんよりひろいですか。)
Is America larger than Japan?

There are 2 patterns of answer form.
The simple form is as below.

Hai Anata Wa Kare Yori Wakai Desu
(はい、あなたはかれよりわかいです。)
Yes, you are younger than him.

Iie Anata Wa Kare Yori Wakaku Arimasen
(いいえ、あなたはかれよりわかくありません。)
No, you are not younger than him.

Another answer form is as below.

Hai Anata Nohouga Wakai Desu
(はい、あなたのほうがわかいです。)
Yes, you are younger.

Iie Kare Nohouga Wakai Desu
(いいえ、かれのほうがわかいです。)
No, he is younger.

You also say as below.

Are Nohouga Kore Yori Oishii Desu
(あれのほうがこれよりおいしいです。)
That is more tasty than this.

Amerika Nohouga Nihon Yori Hiroi Desu
(アメリカのほうがにほんよりひろいです。)
America is larger than Japan?