The sum of the first four terms of an AP is 30 and the sum of the last four terms is 66. If the AP has 7 terms, find the first term and the common difference

When 142 is added to a number the result is 64 more times the number my options are 35 37 39 41

Pepe and leo deposits money into their savings account at the end of the month the table shows the account balances. if there pattern of savings continue and neither earns interest nor withdraw any of the money , how will the balance compare after a very long time ?

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years