Counting methods question How many 4 digit positive integers can be formed without using either '3' or '5'?a. 3584b. 5416c. 6416d. 4096e. 4904Correct Answer : Choice A. 3584Explanatory AnswerWe can count the number of such numbers if we can determine the options available for each of the four digits of the 4-digit number starting with the left most (thousands place).The left … [Read more...] about SAT Counting Methods : Numbers