In an examination of four subjects, a student got 70,80, 90 and x marks and his average was 75. What was the value of x?

If p number of pencils cost c paisa, how many pencils can be bought for taka?

The temperature in a home freezer varies from 25 degree F to 3 degree F. What is the difference, in Celsius, b...

If r=18 and r/s = 6/y, then y/s is ----

If 10% of r is 20% of s. is 20% of s is 30% of t and 100% of r is x% of t, then x is ----

Two third of the faculty members of a department are female. Twelve of the male faculty members are unmarried,...

পিতা ও পুত্রের বয়সের অনুপাত ৭ : ৩। চার বছর পূর্বে তাদের বয়সের অনুপাত ছিল ১৩ : ৫। বর্তমানে পুত্রের বয়স কত?