Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

A 52% bias toss for head using the 51% tail bias coin was done to obtain a fair result.

Can you find how bias is the floor in this case?

My grandson is about as many days as my son in weeks, and my grandson is as many months as I am in years. My grandson, my son and I together are 120 years. Can you tell me my age in years ?

Can you calculate the probability of getting a sum of six when a dice is thrown twice?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

What is the value of 1/2 of 2/3 of 3/4 of 4/5 of 5/6 of 6/7 of 7/8 of 8/9 of 9/10 of 1000?

In the image below, can you find the value of an angle(y)