I play a 6th level storm sorcerer in one of D&D groups, and I just got the boots of striding and springing which increases my jump distance by x3. My strength score is 14 and I have the jump spell, which also increases my jump height by x3. I also have tempestuous magic. So I cast jump then fly ten feet.

Now the way I do the math my maximum long jump distance is about 120 feet (14 x3 x3 +10). And my maximum high jump distance is about 60 feet. (5 x3 x3 +7 (my height) +10)

The initial jump will have that flying added but every other jump for the next ten rounds will be 110/50 feet.

Is my math correct?

Jumping is limited by your normal movement speed

The rules for jumping include this very important clause:

each foot you clear on the jump costs a foot of movement.

This means that you can't jump farther than you can move on a given turn, regardless of your maximum jump distance or height. So, if you have a speed of 30 feet, it doesn't matter what your maximum jump distance is, you can only jump at most 30 feet, either horizontally or vertically. Any effect that increases your speed or otherwise grants you extra movement on your turn (including the dash action) will allow you to jump farther, up to the limits you have calculated: 120 feet for a long jump or 60 feet for a high jump. However, to achieve these maximum jump distances, you will also need 10 more feet of movement to get a running start. So if your maximum jump distance is 120 feet, you actually need 130 feet of movement to make that jump.

Tempestuous magic won't help you

Unfortunately, it seems that the storm sorceror's tempestuous magic feature will probably not help you jump any farther. The feature says:

you can use a bonus action on your turn to cause whirling gusts of elemental air to briefly surround you, immediately before or after you cast a spell of 1st level or higher.

As explained above, what you need is increased movement on your turn, and not only does this feature not provide that, it prevents you from dashing, since you need your action (with rare exceptions) to cast a spell in order to activate the feature. Unless the spell you cast more than doubles your speed, you would be better off taking the dash action instead of casting the spell. So, it seems that this feature is more useful for evading opportunity attacks than for extending jumps.

Without tempestuous magic, by my calculations, your maximum long jump distance will be 126 feet, and your highest high jump will be 45 feet (measured from the ground to the bottom of your feet; add your height as necessary). Both of these assume a 10-foot running start.

There are several mistakes.

Jumping distances and height

If you move at least 10 feet on foot immediately before the jump:

The long jump distance is 14x3x3=126 feet.

The high jump height is (3+2)x3x3=45 feet.

Otherwise, those jump distance and height are halved.

Your character's height (7 feet) does not increase your jump's height, it just lets you grab onto stuff like ledges and branches. For example, you could jump and grab onto a 50 feet high ledge, but you would not be able to jump and land on your feet onto that ledge.

Tempestuous Magic

It does not synergize with casting jump.

You can cast jump and then fly 10 feet with Tempestouous Magic, but you can't jump mid-air so you need to land before you can jump. Moreover, flying is not moving on foot, so you still need to move another 10 feet on foot if you want the full jump.

You can't cast jump, jump, and then fly 10 feet, because Tempestuous Magic only works "immediately before or after you cast a spell of 1st level or higher".

You could possibly jump, fly 10 feet, and then immediately cast jump, but that first jump won't be trippled by the spell.

Problems during combat

Even if your jump distance/height is huge, you are still limited by your movement speed in combat.