A particular element found in nature exists as two stable isotopes. 60.4% of the element has a mass of 68.9257amu, the rest of the element is found with a mass of 70.9249 amu. Calculate the average atomic mass of the element.

Two people toss two coins each. what is the probability that they get the same number of heads?

Mr. Samuel has a few options to consider before deciding what type of car to purchase: 2 functions: manual or automatic 2 capacities: 1600 cc or 2000 cc 3 colors: blue white or grey how many combinations of options does Mr. Samuel need to consider

Find the percent of change from 48 people to 53 people. Round to the nearest tenth of a percent if necessary.

Given the width of the lawnmower is 2.5 feet and the length of the rope is 25 feet, calculate the radius (R) of the pole that will produce a perfect lawn

When seven times a number is decreased by 66 the result is 50. what is the number?

If the sum of a number and nine is doubled , the result is eight less than the number. Find the number.

3 (5b-2) and 8b-5 are they equivalent

Solve the problem - x^2-3x+1 = 0

Jack read a 308-page book in 2 weeks. He read everyday including weekends. How quickly does Jack read?

Find the rate that would be better to solve the problem. Joss makes $60 in 5 days. How long will it take her to make $100? A. Days/Dollars B. Dollars/Days